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Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 3The Relative Proper Motion of G 167-29 in the Constellation BootesFigure 2: Detail of photo from Bruce astrograph of 1961,observatory Landessternwarte Heidelberg-Königstuhl, G167-29 is marked with lines, image was taken from HDAPFigure 3: Detail of POSS2 image of 1994, Oschin Schmidttelescope, Mount Palomar observatory, taken from TheDigitized Skyimages were recorded. Therefore two independentimages can now be analyzed for each record. A thirdtelescope with a focal length of 4 m was used fortracking control. The quality of the scanned Bruceplates is about 1 arc second per pixel. In Figure 1, G167-29 is below the neighborhood stars. Figure 2 isalso from observatory Landessternwarte Heidelberg-Königstuhl. It was made in 1961 by G. Klare. TheBruce astrograph was also used. This time all starswere in line. It is also near the time of closest approachto one of the neighborhood stars. Figure 3 wasmade by the POSS 2 survey in 1994 with the OschinSchmidt telescope and G 167-29 has moved straightthrough the neighborhood stars. The scale of thescanned POSS2 images is also 1.0 arc second perpixel. Figure 4 was made by the author in 2011. An 8inch Newtonian telescope with a webcam was used.The webcam was placed in the primary focus with afocal length of 800 mm. The figure shows the result of100 stacked frames. For scale calibration the distanceof both neighborhood stars was used. These stars(labeled as B and C) show no variations in distance orposition angle over the epoch. The image scale isabout 1.2 arc seconds per pixel.For plotting the relative proper motion, first theposition angle of the measurements is procession cor-Figure 4: Detail of webcam image, made by the author in2011 with 8-inch Newtonian telescope

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 4The Relative Proper Motion of G 167-29 in the Constellation BootesTable 1: G167-29 AB (Position angle is not yet precessioncorrectedSource PA SEP DATEB3473a1914-04-29B3474b1914-04-29B9000a1961-02-15B9001b1961-02-15POSS2/UKS TUred imageAuthor 8-inchNewtonian242.99 24.392 1914.324245.44 24.596 1914.324284.88 17.153 1961.126283.31 17.471 1961.126319.34 20.942 1994.337330.22 24.834 2011.410Table 2: G167-29 AC (Position angle is not yet precessioncorrectedSource PA SEP DATEFigure 5: Photo of the Bruce astrograph made by theauthor in 2009, left astrograph with plate B, right telescopeis for tracking control, behind it is the secondastrograph with plate AB3473a1914-04-29B3474b1914-04-29B9000a1961-02-15131.86 34.267 1914.324132.62 33.963 1914.324104.09 30.518 1961.126B9001b1961-02-15rected to J2000. The maximum correction is about0.15 degree. Then, the data are transformed from polarto Cartesian coordinates. A linear fit is calculated POSS2/UKS TUred imagewith the Gaussian method of least squares. The valueof proper motion was calculated from measurements Author 8-inchNewtonianof 1914 (averaged over the values from both images)and 2011.104.9484.1573.5331.01732.53136.3271961.1261994.3372011.410Table 1 gives the position measurements used inTable 3: G167-29 BC (Position angle is not yet precessioncorrectedthis study for G 167-29 AB, Table 2 gives the positionmeasurements used for the AC components, Table 3gives the position measurements for the BC components.In all cases the position angle is not precessionSource PA SEP DATEB3473acorrected.104.48 47.768 1914.3241914-04-29The proper motion values of this study are givenB3474bby the averaged values of AB and AC (see Figures 6104.07 49.617 1914.3241914-04-29and 7). The result of recalculation of the proper motionfrom these data sets is different to the current104.28 47.703 1961.126B9000a1961-02-15values in literature (see Table 4). In comparison withthe Lowell study the recalculation shows an increasedB9001b1961-02-15angle but a degreased value for proper motion. Comparedwith the LSPM values, the value for proper motionis similar but the direction shows a difference ofPOSS2/UKS TUred image105.77105.2847.77447.6951961.1261994.337about 10 degree. Author 8-inchcalibr. (Continued on page 5)Newtonian103.422011.410

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 5The Relative Proper Motion of G 167-29 in the Constellation BootesFigure 6: Proper motion of G 167-29 AB.Polar coordinates for closest approach:s = 17.7 as; pa= 107.2 degreeTime of closest approach: T0 = 1962.3Proper Motion:μx = -0.103 as/yr; μy = -0.332 as/yr; φ = 197.2 degreeFigure 7: Proper motion of G 167-29 AC.Polar coordinates for closest approach:s = 30.6 as; pa= 285.8 degreeTime of closest approach: T0 = 1956.9Proper motion:μx = -0.097 as/yr; μy = -0.341 as/yr; φ = 195.9 degreeTable 4: The relative Proper motion of G167-29Source date μx μy μ φH.L.Giclas 1964 0.4 193LPSM catalog 2005 -0.046 -0.356 0.359 187.4This study 2011 -0.100 -0.337 0.352 196.6AcknowledgementsThis research has made use of the SIMBAD database,operated at CDS, Strasbourg, FranceThis work made use of the HDAP which was producedat Landessternwarte Heidelberg-Königstuhlunder grant No. 00.071.2005 of the Klaus-Tschira-FoundationReferencesH.L. Giclas, R. Burnham, Jr., N.G. Thomas, 1964,Lowell Proper Motions VI: Proper Motion Surveyof the Nothern Hemisphere with the 13-inch PhotographicTelescope of the Lowell Observatory,Bulletin / Lowell Observatory; no. 124, v. 6 no. 5,p. 135-153.Lepine S., Shara M.M., 2005, A catalog of northernstars with annual proper motions larger than0".15 (LSPM-NORTH catalog), Astron. J., 129,1483-1522.Centre de Données Astronomiques de Strasbourg,SIMBAD Astronomical Database, http://simbad.ustrasbg.fr/simbad/The POSS2 image was taken from The Digitized Sky,Association of Universities for Research in Astronomy,http://stdatu.stsci.edu/cgi-bin/dss_formHDAP, Heidelberg Digitized Astronomical Plates,http://dc.zah.uni-heidelberg.de/lswscans/res/positions/q/form

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 6Astrometric Measurements of the Visual DoubleStar δ BoötisChris EstradaAllen Hancock CollegeAaron Gupta, Manav Kohli, Alyssa Lund, Andrew Stout and Bevin DaglenOregon Episcopal SchoolJ. Joseph DaglenCollege of IdahoAbstract: During the summer 2010 Astronomy Research Seminar at Pine Mountain Observatory, agroup of students from Oregon Episcopal School met with three goals in mind: to learn essential skillsnecessary for astrometry, to observe and measure the double star δ Boötis and compare their results withpublished literature, and to use proper motion vectors to determine the type of double star. The astrometriceyepiece was calibrated using the drift method. The separation and position angle of δ Boötis was determinedrespectively to be 109” and 164.4˚. These where compared with data in the Washington DoubleStar catalog and found to be within 5% of previous measurements.Figure 1: Left to Right:10-inch F6 equatorial scope, Alyssa,Bevin, Andrew, Aaron, Manav, Joseph, and (kneeling) ChrisIntroductionOne of the double star observational teams at thesummer 2010 Astronomy Research Seminar at PineMountain Observatory consisted of students and facultyfrom Oregon Episcopal School in Portland and J.Joseph Daglen, a retired physician and teacher fromCaldwell, Idaho (see Figure 1). They met with theirteam leader, Chris Estrada, for guidance on doublestar observations. The students had very little experiencewith double stars and astronomy. JoeDaglen had previous experience with astronomy andhelped the team by sharing his knowledge.This project’s three goals were:1 . To familiarize students with methods used byastrometrists, including the process of collectingdata, calibrating the eyepiece/telescope using thedrift method, and determining the separation andposition angle of a double star.2 . To give the students the opportunity to maketheir first quantitative measurements and use formulasto estimate the precision of the observations todetermine if the observations were accurate in comparisonto literature data (Johnson, 2008).3 . To determine if the double star is an opticalpair or a gravitationally bound binary system by usingproper motion vectors.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 7Astrometric Measurements of the Visual Double Star δ BoötisThe double star δ Boötis was chosen based on itssizable separation and large disparity in luminositybetween the primary and secondary stars. Such differencesenable the observer to clearly distinguishbetween the two stars (Haas, 2006). By continuouslycollecting data from binary star separations and positionangles over extended periods of time, their orbitsand periods can be determined (Johnson & Genet,2007).CalibrationThe primary goal of the calibration process was todetermine the number of arc seconds represented byeach division on the linear scale of the astrometriceyepiece. Alpha Cephei (Alderamin) was chosen tocalibrate the astrometric eyepiece because its declinationwas between the recommended values of 60° and75°. The calibration star was aligned with the linearscale to begin the drift procedure.The drift method included aligning the calibrationstar with the linear scale, turning off the motor of thetelescope, and then recording the time it took for thestar to travel from the first to the last division(Teague, 2004). Although the entire group was involvedin the drift procedure, only three students conductedeach trial. The first student observed the starthrough the astrometric eyepiece and signaled whenthe star passed through the first and last divisions onthe linear scale. The second student recorded the time(to the nearest 0.01 second) it took for the calibrationstar to pass through the linear scale, while the thirdstudent recorded the data. However, there was onlyone timekeeper and one recorder for the entire calibrationprocess in order to reduce bias. Although thegroup conducted 16 trials, two were omitted due towind interference. The average drift time was 116.3seconds and the standard deviation of the drift timewas found to be 1 second.The group used the drift times to determine thenumber of arc seconds per division on the linear scale(the scale constant) of the astrometric eyepiece. Theequation used to determine the scale constant was:15.0411tcosδZ =60where 15.0411 is the earth’s rotational constant in arcseconds per second, t is the average drift time, cosδ isthe cosine of the declination of the star, and 60 is thenumber of divisions on the linear scale (Estrada et al.,2010). We found that there were 13.4 ± 0.1 arc secondsper division on the linear scale of our telescope,the standard deviation of the scale constant was 0.1arc seconds per division, and the standard error of themean was 0.038 arc seconds per division.SeparationThe separation between the primary and secondarystars was measured by positioning and rotatingthe astrometric eyepiece so that the linear scalepassed through the two stars. The number of divisionsbetween the primary and secondary stars wasestimated to the nearest 0.1 of a division and recorded.To avoid bias, the telescope was adjusted sothat the primary star lay in a different portion of thelinear scale for each trial. A major division on the linearscale was placed between the primary and secondarystars. The division was used as a “zero” pointfrom which divisions were estimated left and right oneach star. The measurements from the “zero” pointwere then added together to yield the total number ofdivisions. A total of sixteen trials yielded an averageof 8.15 divisions between the stars. This figure wasthen multiplied by the scale constant (13.4”/ division)obtained during calibration. Thus, the average separationwas 109”, its standard deviation was 0.44”, andthe standard error of the mean was 0.11”.Position AngleTo obtain position angle using the drift method,the primary star was first set in the center of the linearscale of the astrometric eyepiece (Frey & Frey2010). The clock drive was subsequently disabled, allowingthe primary star to drift toward the protractorscale on the outer ring of the eyepiece. The anglewhere the primary star passed through was recordedto the nearest 0.5 degree. Although 16 trials were recorded,one outlier was eliminated due to novice error.The remaining 15 trials yielded an average of 164.4°,a standard deviation of 0.9°, and standard error of themean of 0.25°. The data was then corrected for theCelestron eyepiece, providing a final position anglemeasurement of 74.4° ± 0.25°.AnalysisAccording to previous literature from the WashingtonDouble Star (WDS) catalog, the last measuredseparation angle for δ Boötis in 2009 was 104.7”, andthe position angle was 78° (Mason, 2010). This study’smeasured separation of 109” is 4.3” (~4.5%) greaterthan those of the last recorded measurement. Themeasured position angle of 74.4° is 3.6° (~4.6%) lessthan the last recorded measurement. According toRonald Tanguay (1998), these differences of less than

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 8Astrometric Measurements of the Visual Double Star δ Boötis5% between our measurements and past measurementssuggest that our data can be considered of reasonableaccuracy.The proper motion vectors cataloged in the WDScatalog from 2009 show the primary star of δ Boötis tohave a proper motion of +85 arc seconds per 1000years in right ascension, and -111 arc seconds per1000 years in declination. The secondary star wasreported to have a proper motion of +84 arc secondsper 1000 years in right ascension and -110 arc secondsper 1000 years in declination (Mason, 2010).This difference of only one milli-arc second per year inboth right ascension and declination strongly suggeststhat the primary and secondary stars are agravitationally bound system moving together through space(Grocheva & Kiselev, 1998).ConclusionsAs mentioned earlier, the goals of this projectwere for students to gather and communicate originaldata regarding the double star δ Boötis, to comparetheir results with previously published literature on δBoötis, and to use proper motion vectors to establishwhether δ Boötis is a true binary or an optical double.During this project, the students learned how togather original data on the double star δ Boötis, andmastered the techniques of telescope collimation andoperation, calibration of an astrometric eyepiece,separation and position angle measurements, anddata analysis.In comparison to previously published literature,the students found that the results of this study canbe considered reasonably accurate due to the differenceof less than 5% between the experimental dataand the literature. Finally, by using proper motionvectors, the students learned to determine whether ornot δ Boötis may be a true binary system.During this project, the students learned manyskills essential to astrometric research. In their effort,the students faced many of the challenges common toastronomers including wind interference and reweightingthe telescope to avoid backlash. They alsocalculated the scale constant for the astrometric eyepieceand conducted statistical analysis to verify thesignificance of their data. Finally, this project allowedstudents to communicate their original findings to thelarger community both through writing a scientificpaper and presenting their results to a large group ofboth students and teachers of astronomy.AcknowledgmentsWe would like to thank Pine Mountain Observatoryfor allowing us to use its facilities; Russell Genet,Richard Berry, Tomas Frey, and Vera Wallen fortheir general assistance and facilitation; and WilliamLamb for providing us with the opportunity to attendthis workshop.ReferencesEstrada, C.; Johnson, J.; Weise, E.; Fisher, J.; Howard,T.; Salam, A.; Almich, C.; Kessinger, D.;Cavanillas, S.; Matakovich, T.; Maly, K.; Wallen,V.; Genet, R. 2010, Journal of Double Star Observations.6, 230–232.Frey, Thomas and Frey, A., 2010, Journal of DoubleStar Observations. 6, 2–4.Grocheva, E and Kiselev, A., 1998, ASP ConferenceSeries. 145, 15–18.Haas, Sissy. 2006, Double Stars for Telescop. Cambridge,MA: Sky Publishing,Johnson, Jolyon M. and Genet, R., 2007, Journal ofDouble Star Observations. 3, 147-150.Johnson, Jolyon. 2008, Proceedings for the 27th AnnualConference of the Society for AstronomicalSciences. 25–27.Mason, Brian. 2010, The Washington Double StarCatalog. Astronomy Department, U.S. Naval Observatory.http://ad.usno.navy.mil/wds/Tanguay, Ronald. 1998, The Double Star Observer’sHandbook. Saugus, MA: Double Star Observer.Teague, Tom. 2004, Observing and Measuring VisualDouble Stars. ed. Bob Argyle. London: Springer.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 9Visual Measurements of a Selected Set of 20Double StarsKodiak Darling, Kristy Diaz, Arriz Lucas, Travis Santo, Douglas WalkerEstrella Mountain Community CollegeAvondale, ArizonaAbstract: The observations and measurements for a selected set of twenty binary starsare reported. These tasks comprised the activities in a continuation of a special mathematicscourse devoted to research techniques being taught at the Estrella Mountain CommunityCollege in Avondale, Arizona. The fall 2010 semester focused on telescope operations,observations and measurements of a selected set of ten binary stars and an analysisof their proper motion. The spring 2011 semester extended the observational sessions andmeasurements to a set of an additional twenty binary stars. In addition, the comparisonof a selected subset of measurements taken with a webcam was compared to visual observations.All observation were taken with a Meade 12” Schmidt Cassegrain Telescope(SCT) using the Celestron MicroGuide TM for measurements.Introduction and InstrumentationThis observation program is part of a specialmathematics class conducted during the fall 2010and spring 2011 semesters at the Estrella MountainCommunity College located in Avondale, Arizona.This mathematics course is designed to give studentsan introduction to performing real-world researchwith the end goal of collecting measurement datawhich is of sufficient quality to be of value to the scientificcommunity. Measurement data collected duringthe fall 2010 semester has been published in theApril 2011 edition of Journal of Double Star Observations,Volume 7 Number 2. The approach and resultsfor the spring 2011 semester observing sessionswere presented at a conference talk at the 30 th AnnualConference on Telescope Science in Big BearLake, California conducted by the Society for AstronomicalSciences. The selection of researching binarystars was chosen since the observation and measurementsof double star systems are an area which canbe achieved with the use of small telescopes.The instrumentation used for observations andmeasurements consisted of a Meade 12” LX200GPSF/10 Schmidt-Cassegrain telescope. This system containedthe GPS feature which made initial setup andcalibration fast and easy. Visual double star measurementswere obtained using the Celestron MicroGuideTM eyepiece which is a 12.5 mm F/L Orthoscopicwith a reticule and variable LED.All observations were taken on the campus ofEstrella Mountain Community College campus locatedat 33 0 28’ 49.46” N, 112 0 20’ 36.47” W duringevening hours which generally consisted of between6:00 and 9:00 PM local time (01:00 to 04:00 UT). Observationsand measurements covered the dates fromlate February 2011 through early April 2011.Selection of StarsAs in fall 2010, the selection of stars for observationand measurement were taken from the WashingtonDouble Star Catalog (WDS). The WDS ismaintained by the United States Naval Observatoryand is the world's principal database of astrometricdouble and multiple star information containing positions(J2000), discoverer designations, epochs, positionangles, separations, magnitudes, spectral types,proper motions and when available, Durchmus-

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 10Visual Measurements of a Selected Set of 20 Double Starsterung numbers and notes for the components of108,581 star systems. The current version of the WDSis updated nightly.The initial approach in fall 2010 was to select aset of target stars from the neglected list on the WDSmain web page. However, in the process of attemptingactual measurement data it was determined thatmany of the stars on the original target list of neglectedstars were beyond the observational capabilitiesof the observing site and the equipment. As resultsof these limitations, the original list was expandedto include a broader range of stars taken fromthe 18-24 hour section of the WDS catalog website.The criteria for observations were modified to the following:• Primary and companion being magnitude 9 orbrighter• At least one magnitude difference betweenthe primary and companion• Separation distance being greater than 5 andless than about 300 arcsecsThis relaxed criteria list proved to be a nice combinationof target stars in need of observation andavailable enough for the telescope equipment. Thisapproach was duplicated for the spring 2011 semesterwith the list of target stars now occupying the skyfrom 5 to 9 hrs RA.Visual Measurements of Selected BinaryStarsDuplicating the approach in fall 2010, the measurementsof the separation distance and position angleof the selected target stars was accomplished usinga standard visual observational approach. Allmeasurements were acquired utilizing the CelestronMicroGuide TM . In order to produce high quality measurements,care was taken in calibrating the measurementinstrument and performing a series of testmeasurements for validation of results before proceedingto the measurements of the target stars.MicroGuide CalibrationCare was taken during fall 2010 to calibrate theCelestron MicroGuide TM in order to obtain the highestprecision measurements. The technique for calibrationwas the standard star drift method with the processbeing carried out over several nights using all observersin order to minimize any observer and instrumentationbias. The approach consisted of locating atarget star of sufficient visual magnitude as close tothe zenith as possible. An observer centered the staralong the microguide’s linear axis and the telescopedrive was temporary switched off to allow the star todrift down the linear scale. After an observer’s timingmeasurement was acquired, the telescope’s drive wasreactivated and the star repositioned to begin anothertiming run. A different observer took the next timingmeasurement. This round-robin approach was appliedto achieve a series of independent measurements foreach observer. These measurements were then averagedto produce the calibration for this observing system.Calibration results for fall 2010 resulted in amean measurement of 38.26 seconds per drift. A histogramdistribution of drift measurement points isshown in Figure 1.The process was repeated for spring 2011 whichresulted in the histogram shown in Figure 2 with amean drift time of 32.21 seconds.A review of Figures 1 and 2 indicates a non Gaussiandistribution of observation measurements wereobtained in fall 2010 and a more symmetric GaussianFrequency987654321037 3 7.2 3 7.4 37.6 37.8 38 38.2 38.4 38.6 38 .8 3 9 39.2Seconds per DriftFigure 1: Histogram of Calibration Measurements – Fall 2010Frequency1210864203131.231.431.631.83232.2Seconds per Drift32.432.632.83333.2Figure 2: Histogram of Calibration Measurements –Spring 201133.4

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 11Visual Measurements of a Selected Set of 20 Double StarsTable 1: Summary Results for MicroGuide TM CalibrationPeriod Average 1 STDFall 2010 38.26 0.38Spring 2011 32.21 0.43type distribution obtained in spring 2011. The meanand the one standard deviation for both calibrationruns are shown in Table 1.Using the standard calibration formula for theMicroGuide resulted in a value of 7.26 arcsecs perMicroGuide grid interval for the fall 2010 measurementsand 7.39 arcsecs per grid interval for spring2011. The difference was attributed to equipmentcalibrations during the time intervals.Measurements ProcessA round robin technique used for taking newmeasurement data was utilized repeating the processused in fall 2010. Separation was measured by orientingthe selected systems along the Microguide’s linearscale, and noting their separation as indicated by thescale’s tick marks. Position angle was then measuredby aligning the binary systems along the linear scale,with the primary star directly on mark 30, and thesecondary along the scale between marks 30 and 60.After the stars were aligned, the telescope’s trackingsystem was temporarily disabled, allowing the binarysystem to drift out of the eyepiece’s field of view. Thebinary system crossed over the circular scale whichruns along the edge of the telescope’s FOV, as thishappened the position of the secondary star along thiscircular scale was noted. 90 degrees were then addedor subtracted from this measurement, dependingupon orientation, to achieve our final Position Anglemeasurements. These processes were repeated severaltimes per system for separation accuracy. Summaryof measurement data are shown in Table 2.Table 2: Summary Data for Measures 2011WDS ID Discover.Magnitudes Last CurrentPrimary Sec Epoch PA SEP Epoch PA SEP08525+2816 HJ 460AC 6.47 6.04 2005 21 273.5 2011.2 20 276.806212+2108 S 513AD 7.31 7.61 2009 24 264.7 2011.2 24 274.707183-3644 JC 10AB 4.66 5.07 1999 98 240.1 2011.2 102 241.608142+1741 STU 22AB-D 6.51 8.94 2002 325 230.1 2011.2 320 230.508476+0001 STU 23AC 7.84 7.82 2004 352 217.3 2011.204 351 219.906047-4505 HJ 3834AC 6.02 6.39 1999 321 196.2 2011.204 323 202.908102+2551 ARN 2AC 6.58 8 2007 22 188.7 2011.204 21 195.507040-4337 DUN 38AC 5.61 8.83 1999 335 184.9 2011.204 337 185.707097+6045 HJL1046AB 6.76 7.95 1999 165 182.2 2011.238 164 184.807013+3225 ARN 66AF 6.59 8.26 2004 301 169.9 2011.238 301 172.008401+2000 ENG 37AB 6.47 6.58 2010 153 148.2 2011.238 151 155.306376+1211 S 529AC 6.91 8.09 2002 168 142.2 2011.238 168 143.007260+1406 STF1088AE 7.38 8.1 1984 224 137.4 2011.244 223 119.608085-1952 S 563AB 7.03 7.62 2002 57 134.3 2011.244 60 140.206255-3504 HJ 3858AB 6.4 7.61 2007 47 131.8 2011.258 48 134.408404-4223 DUN 72AB 6.91 7.8 1999 360 129.8 2011.258 1 130.207478-1601 KNT 4AB 6.54 6.6 2002 132 129.4 2011.258 131 130.807183-3644 JC 10BC 5.07 8.67 1999 216 117.2 2011.263 215 118.906541+0641 STTA 79 7.2 7.52 2004 89 115.5 2011.263 96 117.907254+5633 STTA 84AB 7.72 7.75 2004 324 113.6 2011.263 325 115.0

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 12Visual Measurements of a Selected Set of 20 Double StarsFigure 3: Imagery for S529 ACFigure 4: Imagery for STF1088AVideo Imagery of Selected StarsToward the end of the visual star observing program,a Phillips 900NC video web camera was used toinvestigate capturing imagery of a selected set of thebinary stars. The primary objective of the experimentwas to determine the capabilities of low cost web camerasfor use in obtaining high precision measurementsof double stars. A second objective was to determinewhether a web camera could obtain imageryof doubles with fainter magnitudes than would be observablewith visual means. During an observing sessionconducted over successive nights, 8 binary starpairs were captured. Several examples are describedin detail.Binary S529 AC primary is magnitude 6.91 with asecondary at magnitude 8.09. See Figure 3. The lastmeasurement in the WDS database indicated a separationof 142.2 arc-seconds and position angle of 160degrees. The epoch was 2002.Binary STF1088A primary is magnitude 7.38with a secondary at magnitude 8.1. See Figure 4. Thelast measurement in the WDS database indicated aseparation of 137.4 arc-seconds and position angle of224 degrees with an epoch of 1984.Binary STTA84AB (Figure 5) has a primary atmagnitude 7.72 with a secondary at magnitude 7.75.The WDS database indicates a separation of 113.6 arc-seconds and position angle of 324 degrees with anepoch of 2004.Overall, 8 stars were successfully imaged withmagnitudes ranging from 6.4 up to 8.26. Imaging ofFigure 5: Imagery for STTA84ABfainter stars was not possible with direct video capture.Preliminary analysis utilizing stacking techniqueswas attempted but none were successful. Additionalwork needs to be performed in this area.Analysis of Separation using REDUCREDUC is a software package dedicated to doublestars measurements. The latest version can bedownloaded free on simple demand. It is perfectlyadapted to performing measurements on imagery capturedwith simple CCD and video cameras as demonstratedhere. The main window shown in Figure 6(Continued on page 14)

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 13Visual Measurements of a Selected Set of 20 Double StarsFigure 6: REDUC Main WindowTable 3: Comparison of Visual and Imaged Separation in Arc-secondsSeparation (as)Star WDS Observed Imaged% Accuracyto WDSSTTA 84AB 115 115.5 117.3 98STF1088AE 137.4 119.6 135.2 98

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 14Visual Measurements of a Selected Set of 20 Double Stars(Continued from page 12)provides the ability to load AVI files, select specifictargets and then performs accurate measurementsonce it is calibrated.To provide test data on the utilization of REDUC,star pair S 529AC was loaded and use as a calibrationset. This was applied to star pairs STTA 84AB andSTF1088AE with results shown in Table 3.This limited test shows the promise of using inexpensivevideo imaging equipment for stars brighterthan about magnitude 9. Additional image processingtechniques could be applied to image fainter stars butto what magnitude limit would be obtainable is currentlyunknown.ConclusionThese observations provide additional informationfor researchers to investigate the nature of binarysystems.AcknowledgmentsWe would to thank Becky Baranowski, DepartmentChair for Mathematics, Physics, and Astronomyfor offering this course for the year 2010/2011 and tothe Estrella Mountain Community College for use ofequipment and facilities.References1. Ronald Charles Tanguay, Observing Double Starsfor Fun and Science2. Argyle, Bob, Observing and Measuring Visual DoubleStars, Springer-Verlag London Limited 20043. Sky and Telescope Magazine, March 20114. The Celestron Micro Guide Eyepiece Manual(#94171)

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 15Double Star Measurements at the InternationaleAmateur Sternwarte (IAS) in Namibia in 2009Rainer AntonAltenholz/Kiel, Germanye-mail: rainer.anton"at"ki.comcity.deAbstract: This paper is a continuation of earlier work published in JDSO in 2010. Using a40-cm-Cassegrain telescope in Namibia and a fast CCD camera, 87 double and multiple systemswere recorded and analyzed with the technique of “lucky imaging”. Measurements arecompared with literature data. Some noteworthy systems are discussed in more detail.IntroductionDuring two weeks in September 2009, I used the40-cm-Cassegrain at the Internationale AmateurSternwarte (IAS) in Namibia for observing doublestars in the southern sky [1]. Some measurementshave already been published earlier in this Journal[2]. Results for 87 more systems obtained during thisperiod are presented here.The technique of “lucky imaging” for recordingand measuring double stars is well known, and detailshave been described in earlier papers [2,3].With “lucky imaging”, seeing effects can be drasticallyreduced, and the resolution can be pushed tothe theoretical limit of the telescope. The accuracy ofposition measurements can even be one order ofmagnitude better than this. With a 40-cm telescope,standard deviations of separation measurements ofclose pairs of the order of ±0.05” were obtained.Most of the 87 investigated systems are wellknown, with brightness down to the range of ninthmagnitude, with only a few dimmer ones. Thirty arebinaries with more or less well documented orbits.However, in many cases literature data are scarce,such that estimates of residuals are somewhat ambiguous.For some systems, deviations from predictedmovements could be manifested. Systems, forwhich sufficient and trustworthy literature data exist,are used for calibration of the image scale.InstrumentalThe nominal focal length of the 40-cm Cassegrainis 6.3 m. With my b/w-CCD camera(DMK21AF04, pixel size 5.6 µm square, The ImagingSource), an image scale of 0.187”/pixel was determinedfrom measurements of reference systems, asdescribed earlier. When using a 2x-Barlow lens, thescale was 0.0970“/pix. Almost always, a red filter wasused to reduce seeing effects, as well as the chromaticaberration of the Barlow lens. Exposure timeswere from 0.5 µsec up to 0.1 sec, depending on thestar brightness and the seeing. From recordings ofsome thousands of frames, I usually select the bestones by visual inspection with the program VirtualDub.The typical yield is about 50 to 150 frames,which are re-sampled and aligned with the programRegistax, often with the option “manual”, and finallyautomatically stacked.Calibration and MeasurementsAs described in earlier papers, the image scale isdetermined by measuring a number of doubles withwell known separations. All systems are suitable, forwhich literature data can unambiguously be extrapolatedto the actual date. Main sources are the WDS[4], and the 4 th Catalog of Interferometric Measurementsof Binary Stars [5]. Results for binaries arealso compared with data from the Sixth Catalog ofOrbits of Visual Binary Stars [6]. 22 systems were

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 16Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009found suitable as reference. In the table below, theseare marked with shaded lines. The scale factors citedabove were essentially the same as obtained in earlierwork with the 40-cm telescope, with standard deviationof about ±0.05”. While the accuracy of separationmeasurements is constant, the contribution of thescale factor lets the total error margin increase forgreater separations to up to ±1.0%. The position anglewas deduced from recordings of star trails with thetelescope drive switched off, so as to reveal the actualeast-west-direction in the field of view. The error margindepends on the separation, and ranges from ±0.1 ofor wide pairs up to almost ±4 o for close ones near theresolution limit. All measurements are listed in Table1, and the scatter of the residuals is illustrated in Figures1 and 2 (see below).CommentsMost of the 87 systems presented here are fairlybright and easily accessible with not too small telescopes,which also means suitable for “lucky imaging”.Nevertheless, many of them can be deemed as“neglected”, as there are only few data in the literature.More attention is generally paid to binaries withnot too long periods, for obvious reasons. Twenty-twosystems were found, for which extrapolations of literaturedata of separations appear sufficiently accurate,such that they can be taken for reference. Thestandard deviation of the resulting residuals of about±0.05”, calculated versus the thus determined calibrationconstant, contains both contributions from errorsof own measurements, as well as of literature data, asis the case for the residuals of all other pairs. As wasalready mentioned above, the total, absolute errormargin increases with separation, due to the contributionof the calibration factor with constant relativeerror of ±1.0 %. Some pairs were found noteworthy, beit because of large residuals, which are marked inFigure 2, or for other reasons.- The pair ε Sculptoris (HJ3461 AB, #12) seems tobe physical. A “premature” orbit has been publishedin 1974, but positions strongly deviate, in accordancewith the trend of literature data.- The multiple θ 1 Orionis, the trapezium (STF748, #30), although prominent, has not often beenmeasured. Literature data of separations, both visualand speckle, exhibit large scatter and residuals aresomewhat ambiguous. In contrast, residuals for P.A.are all within the error limits.(Continued on page 23)Figure 1: Plot of the residuals of the position angle versusseparation rho. Note semi-logarithmic scaling. Full rhombsindicate 22 pairs used for calibration, open rhombs all others.Open squares refer to the system θ 1 Orionis, the"trapezium". The increase of scatter towards small separationsis due to the fixed image resolution. The standard deviationfor only the calibration systems is ±0.53 o .Figure 2: Plot of the residuals delta rho versus rho. Notesemi-logarithmic scaling. Full circles indicate pairs used forcalibration, open circles all others. Three of them with residualsexceeding the error limits are marked with their notenumbers. Open squares refer to the system θ 1 Orionis, thetrapezium. The standard deviation for only the calibrationsystems is ±0.047" with range between –0.08" and +0.10".The curves indicate the total, absolute error margins.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 17Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009Table 1: List of measurements. Systems used for calibration are marked with shaded lines. Systemnames, positions and magnitudes are taken from the WDS. The two columns before the last one show thedifferences delta of measured position angles (P.A.) and separations (rho) minus reference data. For severalpairs, no residuals are given because of insufficient reference data. N is the number of measurementsat different nights, or with different camera settings or filters. Individual notes are following thetable. Asterisks denote systems of which images are shown in the figures.PAIR RA + DEC MAGSP.A.meas.rhomeas.DATENdeltaP.A.deltarhoBU 391AB 00 09.4 -27 59 6.13 6.24 258.5 1.38 2009.712 3 -0.4 -0.01 1BU 395 00 37.3 -24 46 6.60 6.20 95.6 0.50 2009.708 3 +3.7 +0.04 2HDO 182 00 42.7 -38 28 6.60 7.01 20.6 0.70 2009.706 2 +0.1 -0.02 3DUN 2 00 52.4 -69 30 6.70 7.35 81.6 20.41 2009.714 1 +0.6 +0.03 4HJ 3416AB 01 03.3 -60 06 7.58 7.67 129.2 5.11 2009.720 2 -0.1 +0.04 5NOTESRST1205AB4.02 6.80 110.0 0.57 2009.722 1 -0.4 +0.0301 08.4 -55 15RMK 2AB-C 4.00 8.23 239.4 6.78 2009.722 1 -2.0 ~06BU 1229 01 19.3 -34 29 8.51 8.74 275.6 0.76 2009.710 1 -1.1 +0.02 7STF 113A-BC 01 19.8 -00 31 6.45 6.99 19.5 1.67 2009.726 1 ~0 +0.03 8HJ 2036 01 20.0 -15 49 7.40 7.61 339.5 2.34 2009.726 1 ~0 +0.02 9HJ 3447 01 36.1 -29 54 5.97 7.35 183.0 0.77 2009.709 2 -2.5 -0.04 10DUN 5 01 39.8 -56 12 5.78 5.90 188.0 11.60 2009.714 2 -0.4 -0.05 11HJ 3461AB 01 45.6 -25 03 5.38 8.50 20.4 5.10 2009.707 2 ~0 +0.26 12HJ 3475 01 55.3 -60 19 7.18 7.23 77.4 2.49 2009.726 1 ~0 ~0 13STF 186 01 55.9 +01 51 6.79 6.84 66.5 0.81 2009.706 2 -0.2 -0.05 14*H 2 58 01 59.0 -22 55 7.28 7.56 302.5 8.77 2009.726 1 +0.5 +0.07 15BU 738 02 23.2 -29 52 7.60 7.97 213.4 1.86 2009.708 1 +1.3 +0.04 16HJ 3506 02 33.8 -28 14 4.95 7.71 245.0 10.80 2009.718 1 ~0 ~0 17BU 741AB8.06 8.20 342.9 0.88 2009.707 1 +0.7 -0.0302 57.2 -24 58S 723AC 8.06 7.68 225.6 29.34 2009.707 1 - -18*HJ 3555 03 12.1 -28 59 3.98 7.19 299.7 5.24 2009.708 1 -0.2 +0.02 19DUN 15 03 39.8 -40 22 6.93 7.72 328.6 7.78 2009.723 1 +0.5 +0.07 20DUN 16 03 48.6 -37 37 4.72 5.25 216.2 8.39 2009.723 1 -0.2 +0.02 21STF 470AB 03 54.3 -02 57 4.80 5.89 349.0 6.98 2009.721 4 +0.3 +0.08 22*BU 184 04 27.9 -21 30 7.40 7.70 248.3 1.87 2009.726 1 ~0 ~0 23HJ 3683 04 40.3 -58 57 7.33 7.45 89.7 3.66 2009.726 1 ~0 +0.04 24STF 590 04 43.6 -08 48 6.74 6.78 318.2 9.38 2009.721 1 +0.2 +0.14 25DUN 18AB 04 50.9 -53 28 5.61 6.24 58.5 12.80 2009.726 1 +0.5 +0.1 26STT 98 05 07.9 +08 30 5.76 6.67 300.4 0.86 2009.710 1 ~0 -0.02 27STT 517AB 05 13.5 +01 58 6.79 6.99 241.0 0.66 2009.710 1 ~0 +0.01 28*STF 728 05 30.8 +05 57 4.44 5.75 44.1 1.25 2009.710 1 -0.8 -0.02 29Table continued on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 18Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009Table 1 continued: List of measurements. Systems used for calibration are marked with shaded lines.System names, positions and magnitudes are taken from the WDS. The two columns before the last oneshow the differences delta of measured position angles (P.A.) and separations (rho) minus reference data.For several pairs, no residuals are given because of insufficient reference data. N is the number of measurementsat different nights, or with different camera settings or filters. Individual notes are followingthe table. Asterisks denote systems of which images are shown in the figures.PAIR RA + DEC MAGSSTF 748ABP.A.meas.rhomeas.DATENdeltaP.A.deltarho6.55 7.49 31.5 9.01 2009.710 1 +0.5 +0.23STF 748AC 6.55 5.06 132.0 12.28 2009.710 1 ~0 +0.08STF 748AD 6.55 6.38 96.1 21.79 2009.710 1 +0.1 -0.39STF 748AE 6.55 11.1 350.6 4.58 2009.710 1 +0.6 -0.2805 35.3 -05 23STF 748BC 7.49 5.06 163.1 17.11 2009.710 1 +0.1 +0.21STF 748BD 7.49 6.38 120.5 19.70 2009.710 1 +0.5 +0.30STF 748CD 5.06 6.38 61.6 13.55 2009.710 1 -0.4 +0.35STF 748CF 5.06 11.5 119.9 4.48 2009.710 1 -1.1 -0.12AGC 1AB 06 45.1 -16 43 -1.46 8.5 90.0 8.78 2009.721 2 -0.1 -0.19 31I 10AB 08 44.7 -54 43 1.99 5.57 302.3 0.57 2009.716 2 ~0 +0.04 32RHD 1AB 14 39.6 -60 50 0.14 1.24 244.2 7.02 2009.714 1 +0.3 +0.02 33SHJ 243AB 17 15.3 -26 36 5.12 5.12 143.4 4.98 2009.718 1 +0.6 +0.03 34BSO 13AB 17 19.1 -46 38 5.61 8.88 255.7 10.19 2009.701 2 ~0 +0.30 35STF2262AB 18 03.1 -08 11 5.27 5.86 284.8 1.54 2009.718 1 -0.2 -0.07 36STF2272AB 18 05.5 +02 30 4.22 6.17 132.3 5.60 2009.718 1 +0.6 -0.08 37H 5014 18 06.8 -43 25 5.65 5.68 3.5 1.78 2009.709 3 +1.2 +0.06 38DUN 222 18 33.4 -38 44 5.58 6.16 358.7 21.73 2009.710 2 +0.3 - 39BSO 14AB 19 01.1 -37 04 6.33 6.58 280.2 13.05 2009.710 1 - - 40HJ 5075 19 04.1 -63 47 7.68 7.69 112.5 1.74 2009.721 1 -0.5 -0.06 41HJ 5084 19 06.4 -37 04 4.53 6.42 13.3 1.37 2009.708 3 ~0 +0.03 42GLE 3 19 17.2 -66 40 6.12 6.42 343.4 0.53 2009.716 2 +0.7 +0.01 43DUN 226 19 22.6 -44 28 3.98 7.21 76.0 28.7 2009.714 1 - - 44SCJ 22 19 28.2 -12 09 8.12 8.69 275.0 0.93 2009.705 1 -3.0 -0.02 45S 722 19 39.2 -16 54 7.17 7.45 235.9 10.02 2009.714 1 +0.2 +0.04 46HJ 599AB5.31 12.6 279.2 45.2 2009.714 1 - -19 40.7 -16 18 47*HJ 599AC 5.42 7.65 41.6 45.6 2009.714 1 - -DUN 227 19 52.6 -54 58 5.80 6.39 147.9 23.28 2009.721 1 -0.3 +0.10 48STF2594 19 54.6 -08 14 5.65 6.35 170.2 35.55 2009.718 1 -0.1 ~0 49HDO 295 20 11.1 -57 31 6.76 7.68 283.5 0.46 2009.721 1 +2.9 +0.04 50RMK 25 20 14.9 -56 59 7.97 8.02 28.1 7.23 2009.721 1 -0.9 +0.1 51DUN 230 20 17.8 -40 11 7.42 7.72 117.7 9.69 2009.714 1 +0.7 ~0 52SHJ 323 AB 20 28.9 -17 49 4.97 6.88 191.3 1.50 2009.705 4 +1.2 -0.11 53SHJ 324 20 29.9 -18 35 5.91 6.68 238.2 21.89 2009.718 1 +0.2 +0.10 54NOTES30Table continued on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 19Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009Table 1 conclusion: List of measurements. Systems used for calibration are marked with shaded lines.System names, positions and magnitudes are taken from the WDS. The two columns before the last oneshow the differences delta of measured position angles (P.A.) and separations (rho) minus reference data.For several pairs, no residuals are given because of insufficient reference data. N is the number of measurementsat different nights, or with different camera settings or filters. Individual notes are followingthe table. Asterisks denote systems of which images are shown in the figures.PAIR RA + DEC MAGSP.A.meas.rhomeas.DATENdeltaP.A.deltarhoHU 200AB 20 39.3 -14 57 5.38 7.31 121.6 0.34 2009.710 1 +1.4 +0.01 55S 763AB 20 48.4 -18 12 7.24 7.79 293.5 15.64 2009.718 1 -0.3 +0.08 56STF2729AB 20 51.4 -05 38 6.40 7.43 23.8 0.83 2009.697 1 -2.6 +0.05 57RMK 26 20 51.6 -62 26 6.23 6.58 80.6 2.44 2009.720 2 -0.6 -0.01 58HJ 3003 20 53.0 -23 47 6.57 8.57 194.4 1.53 2009.710 1 -0.9 -0.03 59H 1 47 21 12.4 -15 00 8.25 8.31 309.8 4.15 2009.718 1 +0.7 -0.03 60HJ 5258 21 19.9 -53 27 4.50 6.93 269.5 7.32 2009.721 4 -1.3 +0.1 61*BU 252 21 20.0 -27 18 8.75 8.84 88.1 2.17 2009.708 1 ~0 +0.02 62BU 766AB 21 24.4 -41 00 6.24 6.88 197 ? 0.18? 2009.723 1 -3.0 -0.02 63BU 1212AB 21 39.5 -00 03 6.94 8.44 286.1 0.50 2009.697 1 -1.0 +0.01 64HDO 296AB 21 55.2 -61 53 6.6 6.8 106.4 0.33 2009.724 2 +1.1 -0.02 65BU 276 22 00.8 -28 27 5.70 6.77 112.6 1.86 2009.710 1 ~0 ~0 66H N 56AB 22 14.3 -21 04 5.63 6.72 112.2 5.23 2009.720 8 +0.8 - 67I 20 22 18.0 -62 49 7.36 8.42 187.8 0.64 2009.721 1 ~0 +0.02 68BU 172AB 22 24.1 -04 50 6.45 6.63 38.7 0.38 2009.705 1 -1.4 ~0 69*PZ 7AC 22 31.5 -32 21 4.28 7.12 172.1 30.6 2009.713 3 - - 70DUN 241 22 36.6 -31 40 5.93 7.55 31.6 93.9 2009.714 1 +0.2 +0.10 71BU 773 23 06.9 -38 54 5.70 8.24 205.0 0.93 2009.710 1 -0.2 -0.02 72JC 20AB 23 06.9 -43 31 4.45 6.60 113.9 1.50 2009.707 2 -1.0 -0.05 73DUN 246 23 07.2 -50 41 6.29 7.05 253.9 8.99 2009.703 1 -0.4 +0.12 74HU 295 23 22.7 -15 02 5.59 6.72 281.5 0.35 2009.704 3 -0.4 +0.02 75STF3008 23 23.8 -08 28 7.21 7.67 149.3 6.60 2009.726 1 -0.2 +0.10 76DUN 249 23 23.9 -53 49 6.14 7.07 211.4 26.5 2009.714 1 -0.6 +0.10 77I 23 23 28.2 -56 26 7.58 8.91 353.6 0.68 2009.694 1 -0.4 -0.12 78B 1900 23 33.3 -20 55 4.76 7.68 127.8 0.96 2009.726 1 - -79I 25 23 35.3 -57 30 8.45 8.43 25.0 0.70 2009.694 1 +3.2 -0.05 80*SEE 492 23 35.7 -27 29 6.84 9.18 17.2 0.63 2009.694 1 -2.8 +0.03 81*DUN 251 23 39.5 -46 38 6.53 7.27 277.6 3.88 2009.694 1 +0.5 ~0 82HU 1550 23 41.5 -41 35 8.45 8.71 194.6 0.73 2009.694 1 +2.7 -0.04 83H 2 24 23 46.0 -18 41 5.65 6.46 135.7 6.98 2009.714 1 ~0 +0.08 84SLR 14 23 50.6 -51 42 8.28 8.59 72.8 0.87 2009.708 4 -0.7 -0.01 85*LAL 192 23 54.4 -27 03 6.79 7.41 268.9 6.44 2009.718 1 -1.1 +0.06 86LAL 193 23 59.5 -26 31 8.05 8.30 169.5 10.63 2009.718 1 ~0 +0.03 87NOTES

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 21Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009with last entries in the speckle catalog from2002 to 2008, reason unknown.31. α Canis Majoris, “Sirius”, binary, P=50.1y, residualsvs. ephemeris.32. δ Velorum, binary, P=142y, difficult, becausedim companion on diffraction ring, residualsvs. ephemeris.33. α Centauri, binary, P=79.9y, residuals vs.ephemeris.34. 36 Ophiuchi, binary, “premature” orbit,P=550y.35. in Ara, also known as L7194, binary, P=693y,few data, recent measurements tend to deviatefrom calculated orbit.36. τ Ophiuchi, binary, P=280y, many speckledata, residuals given vs. trend.37. 70 Ophiuchi, binary, P=88.3y, many speckledata with small scatter.38. in Corona Australis, binary, P=191y, residualsvs. ephemeris.39. κ Coronae Australis, relfix, few data with largescatter, residual of rho ambiguous.40. in Corona Australis, large scatter of literaturedata, no residuals given.41. in Pavo, few data.42. γ Coronae Australis, binary, P=122y, PA dec.43. in Pavo, binary, P=157y.44. β Sagittarii, large scatter of literature data.45. in Sagittarius, also know as BU 142, binary,P=162y, many speckle data with relativelysmall scatter. Residuals given vs. speckle dataof about the same epoch.46. in Sagittarius, few data with large scatter.47. 54 Sagittarii, no recent literature data of AB,large scatter of data for AC, no residualsgiven. Dim companion of about 13 th magnitudeat 252.3 o /56.8” not listed in the WDS.See Figure 5.48. in Telescopium, cpm, few data, PA dec, rhoslow inc.49. 57 Aquilae, relfix.50. in Pavo.51. in Pavo.52. in Sagittarius, PA inc, rho almost fixed.53. rho Capricorni, binary, P=278y, orbit highlyinclined, own measurements, as well as literaturedata seem to deviate from ephemeris,Figure 4: The triple system BU 741 AB/S 723 AC in Fornax.The pair AB is a physical binary with period 137 y. See alsonote 18.Figure 5: The multiple HJ 599 or 54 Sagittarii. The seeingallowed for 2 sec exposure, superposition of 40 frames. Thedim companion at upper left, which is marked with blacklines, is not listed in the WDS. See also note 47.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 22Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009residuals given vs. ephemeris.54. ο Capricorni.55. τ Capricorni, binary, P=200y, peculiar scatterof literature (speckle) data, residuals given vs.ephemeris.56. in Capricornus, relfix.57. 4 Aquarii, binary, P=187y, recent rho dataseem to deviate from ephemeris, residualsgiven vs. ephemeris.58. in Pavo, also known as L8550, cpm, PA dec.59. in Capricornus, PA fast, rho slowly dec.60. in Capricornus, probably binary, ephemerisquestionable, residuals vs. speckle data from2009.61. θ Indi, cpm, PA slow dec?, rho fast inc, nicecolor contrast, see Fig.6.62. in Capricornus, PA and rho dec..63. in Microscopium, not resolved here, but elongated,PA and rho estimated, both are decreasing,residuals vs. trend of literature data,last entry in speckle catalog from 1999.64. 24 Aquarii, binary, P=49y, many speckle datawith small scatter.65. in Indus, binary, P=27.5y, orbit highly inclined,few data.66. η Piscis Austrini, relfix, PA dec.67. 41 Aquarii, few data with large scatter, especiallyfor rho, PA dec, color contrast.68. in Tucana, binary, P=983y, PA decreasing, rhoslowly inc, residuals estimated vs. trend.69. 51 Aquarii, binary, P=146y, residuals vs.speckle data from 2009.70. β Piscis Austrinus, cpm, relfix, few data withlarge scatter, no residuals given.71. in Piscis Austrinus, optical, few data, rhoseems to linearly increase.72. υ Gruis, few data, PA and rho decreasing,some earlier speckle data show peculiar scatter,residuals vs. trend.73. θ Gruis, cpm, both PA and rho seem to linearlyincrease.74. in Grus, PA slowly decreasing, rho inc.75. 97 Aquarii, binary, P=63y, residuals vs.ephemeris.76. in Aquarius, optical, residuals vs. rectilinearextrapolation.77. in Grus, few data.78. in Phoenix, PA inc, few data.79. in Aquarius, few data with large scatter, noresiduals given.80. in Phoenix, PA dec.81. in Sculptor, binary, P=78y, difficult, becausedim companion is close to diffraction ring ofmain star, not resolved with speckle interferometryin 2008, PA fast inc.82. θ Phoenicis, PA increasing, rho slowly decreasing?83. in Phoenix, few data with large scatter, PAand rho increasing?84. 107 Aquarii, rho slow inc?85. in Phoenix, binary, P=117y, PA fast dec, rhofast inc.Figure 6: Two colorful doubles: Left: 32 Eridanis, spectra areG8III and A2V. Description of colors in the literature rangefrom grapefruit-orange and silvery-blue to topaz-yellow andsea green. Right: theta Indi. A not so frequent case of a redcompanion to a main sequence star. Spectral class of the latteris A5V, that of the companion is not listed. Colors are describedin the literature as light-yellow and reddish-brown.See also notes 22 and 61.86. φ Sculptoris, also known as DUN 253, relfix.87. also known as Arg 46, few data, PA and rhoslowly dec.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 23Double Star Measurements at the Internationale Amateur Sternwarte (IAS) in Namibia in 2009(Continued from page 16)- For the binary BSO 13/L 7194 in Ara (#35), withperiod of about 700 years, only few data are availablein the literature. Recent measurements of the separationtend to deviate from the ephemeris from 1957.- The binary rho Capricorni (SHJ 323 AB, #53)exhibits a highly inclined orbit. Both own measurementsand literature data tend to deviate from thecurrently assumed ephemeris.- The close pair 4 Aquarii (STF 2729 AB, #57) is abinary with period 187 years. Separation measurestend to be greater than expected from the ephemerisby about 0.05”, in accordance with literature data.- Residuals for the pair H I 47 in Capricornus(#60) are within the error limits, when referred to recentspeckle data, but strongly deviate from theephemeris published in 1974. With an estimated periodof more than 4000 years, this seems to be in error.References[1] IAS, www.ias-observatory.org[2] Anton, R., 2010, Journal of Double Star Observations,vol. 6 (2), 133-140.[3] Anton, R., 2009, Journal of Double Star Observations,vol. 5 (1), 65-71.[4] Mason, B.D. et al., The Washington Double StarCatalog (WDS), U.S. Naval Observatory, onlineaccess July 2011.[5] Hartkopf, W.I. et al., Fourth Catalog of InterferometricMeasurements of Binary Stars, U.S. NavalObservatory, online access July 2011.[6] Hartkopf, W.I. et al., Sixth Catalog of Orbits ofVisual Binary Stars, U.S. Naval Observatory,online access July 2011.[7] Burnham´s Celestial Handbook, R. Burnham, Jr.,Dover Publications, New York 1978.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 24Chico High School Students' AstrometricObservations of the Visual Double Star STF 1657Jonelle Ahiligwo 1 , Clara Bergamini 1 , Kallan Berglund 1 , Mohit Bhardwaj 1 ,Spud Chelson 1 , Amanda Costa 1 , Ashley Epis 1 , Azure Grant 1 , Courtney Osteen 1 ,Skyla Reiner 1 , Adam Rose 1 , Emily Schmidt 1 , Forest Sears 1 , Maddie Sullivan-Hames 1 , andJolyon Johnson 21. Chico Senior High School, California2. Gateway Science Museum, California State University, ChicoAbstract: In the spring of 2011, Chico Senior High School students participated in an astronomyseminar at the Gateway Science Museum, University of California, Chico. The observersused a Celestron NexStar 6 SE telescope and a Celestron MicroGuide eyepiece todetermine the separation and position angle of the visual double star STF 1657. Observationswere made in approximately one hour on the evening of May 1, 2011. The observersdetermined that the separation of STF 1657 was 22.1” and the position angle was 273.4°.Seminar members then used the spectral type, parallax, and proper motion vectors of thetwo stars to determine if they are a line-of-sight optical pair or physically bound by gravity.Due to large errors in the parallax and the proper motion vector for the secondary star, theresults were inconclusive. Through this experience, the students learned the skills needed toobserve, analyze, and report on double stars.IntroductionIn the spring of 2011 Jolyon Johnson led an astronomyresearch seminar of fourteen enthusiasticstudents from Chico Senior High School, California.The seminar was offered through the Gateway ScienceMuseum at California State University, Chico,and focused on the study of visual double stars. Itfollowed a model developed at Cuesta College in SanLuis Obispo, California and the University of Oregon'sPine Mountain Observatory (Johnson 2007,Genet et al. 2010a, Genet et al. 2010b).The goals of the seminar were both scientific andeducational. The scientific goals were to: 1) contributeobservations to the Washington Double Star(WDS) catalog, and 2) determine whether or not thisdouble star is likely a chance optical line-of-sightFigure 1: Students gathered at the Gateway Science Museum onthe evening of May 1, 2011 to observe the double star STF 1657with a Celestron NexStar 6 SE telescope and a Celestron MicroGuideeyepiece.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 25Chico High School Students' Astrometric Observations of the Visual Double Star STF 1657double or a binary star bound by gravity. The educationalgoals were to: 1) gain a better understanding ofastronomy through hands-on experience, 2) learn andapply a method for measuring the separation and positionangle of a double star, and 3) learn the processfor analyzing data and writing and editing a scientificpaper.MethodsThe students searched the WDS catalog to identifyobservable stars based on their magnitude andseparation. The stars had to be bright enough and farenough apart to observe in a 6-inch telescope andbright city skies. The visual double star STF 1657 fitthe criteria with a primary magnitude of 5.1, a secondarymagnitude of 6.3, and separation of 19.9 arc seconds(Mason 2008). Observations were made on May1, 2011 (B2011.353) with a Celestron NexStar 6 SEtelescope and a 12.5 mm illuminated Celestron MicroGuide eyepiece.Several past seminars have used the same telescopeand eyepiece as the present study to observedouble stars. The scale constants they derived wereaveraged and used in the present study. Table 1shows the three scale constants used, their average,standard deviation, and standard error of the mean.The mean error of 0.1”/div is significantly less thanthe mean observational error.The separation of the two stars was estimated tothe nearest 0.1 division on the linear scale (Teague2004). Each student noted at least one observationand whispered it to a designated recorder so otherscould not hear, thus preventing bias. A total of 12measurements were made. Three outliers were excludedfrom the mean because they were more thanthree times the standard deviation from the average.These outliers were due to the stars drifting awayfrom the linear scale because of polar misalignment.The mean distance in divisions was multiplied by thescale constant of 12.3 arc seconds per division to convertthe measured value into arc seconds. The studentsthen calculated the standard deviation andstandard error of the mean of this separation.The drift method was used to measure the positionangle between celestial north and the secondarystar with the primary star at the vertex (Teague2004). First the primary star was centered at the midpointof the linear scale and the eyepiece was rotateduntil the secondary star was between the parallellines of the scale. The RA motor was then disabledand the stars drifted toward the outer protractor.Where the primary star crossed the protractor wasnoted to the nearest degree and secretly told to therecorder to avoid bias. A 90° position angle correctionwas added to the measurements as is required for theCelestron MicroGuide eyepiece (Teague 2004). A totalof 10 measurements were made and their average,standard deviation, and standard error of the meanwere calculated with one outlier rejected because itwas more than three times the standard deviation.The outlier was precisely 20° off and likely the resultof misreading major divisions.Observational ResultsTable 2 shows the results of the separation andposition angle measurements including the averages,standard deviations, standard errors of the mean, andthe average of three catalog values, the first and lastfrom the WDS Catalog and one from Eagle Creek Observatory(Mason 2008 and Muenzler 2003).The difference between the observed and averagecatalog separation value of 1.8” is higher than wouldbe expected—four times the standard error of theTable 1: The measured scale constants of past researchseminars using the NextStar 6 SE and CelestronMicroguide eyepiece used in the present study.Scale constant(arc seconds per division)Baxter et al. 2011 12.2Brashear et al. 2011a 12.5Brashear et al. 2011b 12.2Average 12.3Table 2: The averages, standard deviations, and standarderrors of the mean for the separation and positionangle compared to catalog values.SeparationPosition AngleObserved Catalog Observed CatalogAverage 22.1” 20.3” 273.4° 272°St. Dev. 1.2” 0.4” 0.5° 1.7°Mean Err. 0.4” 0.2” 0.2° 1.0°St. Dev. 0.2Mean Err. 0.1

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 26Chico High School Students' Astrometric Observations of the Visual Double Star STF 1657mean of 0.4”. The maximum for the catalog values isstill 0.2” different from the minimum observed value.If the minimum scale constant of 12.2”/div is used, theaverage separation is 22.0”. This is still four times thestandard error of the mean away from the average ofcatalog values. The authors attribute the differenceprimarily to polar misalignment (which caused thestars to drift away from the linear scale) or other systematicerrors.The observed position angle was also significantlydifferent from the average catalog value. The differenceof 1.4° is 7 times the standard error of the meanof 0.2°. However, there is overlap between the maximumcatalog values and minimum observed value.The difference may have been caused by an imprecisealignment of the stars on the linear scale.System AnalysisThe students referenced the SIMBAD (2011) databaseto determine whether or not the stars could bea gravitationally bound binary. The pair of stars selectedhas the WDS designation of STF 1657, whichcorresponds to HD 109511 and HD 109510 for theprimary and secondary stars, respectively. To determineif it is possible that the two stars are bound bygravity, we first compared the spectral types and apparentmagnitudes of the two stars. The primary staris spectral type K2III and has a primary magnitude of5.11, making it likely to be a red giant. The secondarystar is on the main sequence with spectral type A9Vat magnitude 6.33. It is difficult to estimate howbright a red giant should be compared to an intrinsicallybright main sequence star, so a more quantitativeanalysis had to be made.The group then attempted to calculate the actualdistance to the two stars from Earth based on theirrespective trigonometric parallaxes. The distance inlight years can be calculated as the inverse of the parallaxin arc seconds multiplied by 3.26 (the number oflight years in one parsec). The parallax of the primarystar is 0.00531 arc seconds which corresponds to adistance of 614 light years. The parallax of the secondarystar is 0.00124 arc seconds which corresponds toa distance of 2,629 light years. While this would certainlysuggest the stars are not bound by gravity, theerror statement of the secondary star's parallax is0.00991 arc seconds. The secondary star could be infinitelyfar away (since there cannot be a negative parallaxthe minimum value is 0.0 arc seconds) or asclose as 292 light years. This range of values makesthe calculated distance unreliable. Therefore, wecould not use the distance estimates to determine thelikelihood that the stars are bound by gravity.Finally, the students analyzed the proper motionvectors of the two stars to determine if they are travelingthrough space in approximately the same direction.Most binary star components have proper motionvectors within 10% of each other (Arnold 2010).Table 3 shows the proper motion vectors of the twostars of STF 1657.While the vectors appear different, the errors forthe secondary star are very large, 25.11 milliarcsecondsper year (mas/yr) in RA and 15.97 mas/yrin dec. Thus the secondary star could be traveling asslow as -0.29 mas/yr in RA and as high as 28.75 mas/yr in dec. Additionally, the error in RA for the primarystar is 2.12 mas/yr giving a maximum value of -2.46 mas/yr. With the errors taken into account, thetwo stars can be shown to travel essentially in thesame direction through space. Yet, this can only bedone with the extremes of the uncertainties, makingit possible, though unlikely, that the stars are movingin the same direction.Table 3: Proper motion vectors for the primaryand secondary starsRA (mas/yr)Dec (mas/yr)HD 109511 -4.58 23.30HD 109510 24.82 12.78ConclusionsDue to the large error margins reported for thetrigonometric parallax and proper motion vectors inthe SIMBAD database for HD 109510, it is uncertainwhether or not the system is bound by gravity. Moreprecise parallax and proper motion vectors may helpdetermine if the stars do, in fact, orbit one another. Ifthis is proven, continued research may yield the semimajoraxis, orbital period, and stellar masses. Thoughit could not be determined if the system was binary,the seminar proved a valuable learning experience.The students also learned some frustrations associatedwith astronomical observing. For example, theprime observing time happened to be the evening beforea full moon so a new observing night had to bescheduled. This second evening was found to becloudy in local weather forecasts. Thus, the observingnight had to be on a school night in May when astronomicaltwilight did not occur until approximately9:00 and everyone had to leave by 10:00. Observations

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 27Chico High School Students' Astrometric Observations of the Visual Double Star STF 1657had to be limited to just the double star unlike previousseminars that also determined the scale constantfor the linear scale. Once sufficient separation andposition angle measurements were taken, observingtime was over. The students are hopeful that theseparation and position angle values they determinedmay be added to the WDS catalog and used by futureresearchers if STF 1657 proves to be binary.On the evening of observations, the studentslearned how to polar align the NexStar 6 SE, applythe astrometric vocabulary they learned during theseminar, and avoid potential research biases. The followingmeetings taught students how to turn simplemeasurements into meaningful data by using basicstatistics. Finally, the students learned the tools astronomersuse to identify binary stars and compiledthe information into a research paper. Such skills areinvaluable to high school and undergraduate studentsheaded for careers in science.AcknowledgmentsThe authors would like to thank the Gateway ScienceMuseum at California State University, Chicoand Director Rachel Teasdale for hosting the seminar.The students also thank Russ Genet at CaliforniaPolytechnic State University for advising the seminar,loaning the telescope used in the project, and forreviewing the paper. The authors would also like tothank Celestron who donated the eyepiece, equatorialwedge, and tripod to student research. The authorsfinally thank Dave Arnold and Tom Frey for theirhelpful reviews.ReferencesArnold, Dave, 2010, “Considering Proper Motion inthe Analysis of Visual Double Star Observations”in Small Telescopes and Astronomical Research.Eds. Russ Genet, Jolyon Johnson, and VeraWallen, Santa Margarita, CA: Collins FoundationPress.Baxter, Alexandra, et al., 2011, “Comparison of TwoMethods of Determining the Position Angle of theVisual Double Star 61 Cygni with a Celestron MicroGuide Eyepiece”, Journal of Double Star Observations,7, 212.Brashear, Nicholas, et al., 2011a, “Measurements andAnalysis of the Visual Double Star STF 1919 atthe 2010 Oregon Star Party.” Journal of DoubleStar Observations, Submitted.Brashear, Nicholas, et al., 2011b, “Observations,Analysis, and Orbital Calculation of the VisualDouble Star STTA 123 AB.” Journal of DoubleStar Observations, Submitted.Genet, Russell, et al, 2010a, “One-Semester AstronomicalResearch Seminars” in Small Telescopesand Astronomical Research, Eds. Russ Genet,Jolyon Johnson, and Vera Wallen, Santa Margarita,CA, Collins Foundation Press.Genet, Russell, et al, 2010b, “Pine Mountain ObservatorySummer Research Workshop” in Small Telescopesand Astronomical Research, Eds. RussGenet, Jolyon Johnson, and Vera Wallen. SantaMargarita, CA, Collins Foundation Press.Johnson, Jolyon, 2008, “Double Star Research as aForm of Education for Community College andHigh School Students” in Proceedings for the 27 thAnnual Conference for the Society for AstronomicalSciences, Eds. Brian Warner, Jerry Foote,David Kenyon, and Dale Mais.Mason, Brian, 2011, The Washington Double StarCatalog, Astrometry Department, U.S. Naval Observatory.http://ad.usno.navy.mil/wds/wds.html.Muenzler, Kevin, 2003, “Double Stars in Coma Berenices.”,Eagle Creek Observatory. http://www.eaglecreekobservatory.org/eco/doubles/com.html.SIMBAD Astronomical Database, 2011, Centre deDonnées Astronomiques de Strasbourg, http://simbad.u-strasbg.fr/simbad/.Teague, Tom, 2004, “Simple Techniques of Measurement”in Observing and Measuring Visual DoubleStars, Ed. Bob Argyle. London, Springer.Jonelle Ahiligwo, Clara Bergamini, Kallan Berglund, Mohit Bhardwaj, Spud Chelson, Amanda Costa,Ashley Epis, Azure Grant, Courtney Osteen, Skyla Reiner, Adam Rose, Emily Schmidt, Forest Sears,and Maddie Sullivan-Hames are physics students at Chico Senior High School. Jolyon Johnson is asenior geology major at California State University, Chico. He is a docent at the Gateway ScienceMuseum and led the spring astronomy seminar.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 28A New Companion for STF 2590,WDS 19523+1021Micello GiuseppeBolognaEmilia Romagna, Italy7mg8@libero.itAbstract: A new companion in Struve 2590 (WDS 19523+1021STF 2590) is described.This is a multiple star in the constellation Aquila and is composed of four components. Thenew component, identified in CCD images, is not present in the WDS.IntroductionOn August 12, 2011 I ran some footage CCD tomake some routine astrometric measurements ofdouble stars in the W. Struve catalog.Consulting the Washington Double Star Catalog,I noticed that STF 2590 (WDS 19523+1021, R.A. 1952 15.58; DEC. +10 21 05.8) has four components,but the CCD images show a new component E (Mv13.5) for this multiple star system.MethodsFor STF 2590, as shown in Table 1, the WashingtonDouble Star Catalog (WDS) lists the measuresfor the AB, AC and CD pairs, but no measurementfor an E component. CCD images, however, show astar near the B component of this multiple star system.The Aladin Sky Atlas (catalogs "SDSS-DR7,PPMXL, NOMAD1 e 2MASS-PSC") and the 2MASS-PSC indicate that this star is “12521526+1021199”with a visual magnitude of 13.5.The latest measures of the Washington DoubleStar Catalog were made in 2000 for the pair AC andin 2007 for pairs AB and CD.I consulted the articles published in the Journalof Double star Observations (www.jdso.org) andfound that Edgardo Rubén Masa Martin, in 2007,performed astrometric measurements for the AB andCD pairs [Masa Martin, 2009]. In note 96, in thesame article, Masa states that component A is a variablestar.Figure 1 shows an image of STF 2590 with the Ecomponent, obtained with Schmidt-Cassegrain telescope200/2000.Astrometric Measurements and DataAnalysisThe astrometric measurements were performedwith the software REDUC (By Florent Losse) andthe calibration star used was STF 2777 (WDS21145+1000STF 2777; Theta: 6° - Rho: 74,1”).The telescope used was a Schmidt-Cassegarin200/2000 on German equatorial mount and the opticaltrain was composed of CCD Camera DMK 21AUwith IR/UV cut filter.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 29A New Companion for STF 2590, WDS 19523+1021Table 1: Astrometric measurements of STF 2590 from the WDSNameID WDSTheta Rho Mv1 – Mv2 EpochCoordinate WDSR.A.DEC.STF 2590 AB19523+1021309° 13.5” 6.50 - 10.31 2007 19 52 15.58 +10 21 05.8STF 2590 AC19523+1021309° 115.3” 6.50 – 11.6 2000 19 52 15.58 +10 21 05.8STF 2590 CD19523+1021272° 8.3" 11.6 – 12.2 2007 19 52 09.50 +10 22 18.3Figure 1: Image of STF 2590 showing the E component. Image by the author.As shown in Table 2, I updated the measurementsfor the pairs AB, AC and CD and performed, for thefirst time, the measurements for the pair AE: Theta:= 342.34° and Rho = 15.057”The catalog 2MASS-PSC catalog gives the qualityflag "AAA", indicating the best quality JHK magnitudeswhich are: J - H - K = 12.608 - 12.352 - 12.328and a visual magnitude of 13.5. Unfortunately, noproper motion for this star is reported in the 2MASS-PSC, NOMAD1 and PPMXL catalogs.The SDSS-DR7 catalog, indicates the componentE as: “class 6 = Star: A a self-luminous gaseous celestialbody”. Figure 2 gives the astrometric data fromthe SDSS (Sloan Digital Sky Survey - http://cas.sdss.org/astro/en/tools/explore/).(Continued on page 31)

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 30A New Companion for STF 2590, WDS 19523+1021Table 2: New astrometric measurements of STF 2590 AB, AC, and CD. First measurements new pair AE and probable newname.Name andID WDSThetaRhoMv1 – Mv2WDSEpochR.A.Coordinate WDSDEC.STF 2590 AB19523+1021STF 2590 AC19523+1021STF 2590 CD19523+1021309.5° 13.55” 6.50 - 10.31 2011.6113 195215.58 +102105.8309.3° 114.09” 6.50 – 11.6 2011.6113 195215.58 +102105.8272.1° 8.21” 11.6 – 12.2 2011.6113 195209.50 +102218.3New Pair AE Theta Rho Mv1 – Mv2 EpochR.A.Coordinate WDSDEC.AE(19523+1021)342.3° 15.05” 6.50 - 13.5 2011.6113 195215.58 +102105.8Figure 2: Screen shot of SDSS astrometric data on the new E component.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 31A New Companion for STF 2590, WDS 19523+1021(Continued from page 29)ConclusionsOne of the main questions is why has the E componentnot been cataloged? The article by Masa E. R.indicates the A component is a variable star, thereforeit may be that the E component was not seen forthe variability of the principal component. But a variablestar may be the same component E, object ofstudy for the next steps.AcknowledgmentsI thank the Washington Double Star Catalog andthe Journal of Double Star Observations for the information.I thank Florent Losse for excellent softwareReduc. This work made use of the catalogs of TheAladin Sky Atlas.A special thanks to Adriano Dragone for the helpand advice.ReferencesBrian D. Mason, Gary L. Wycoff, and William I. Hartkopf.Washington Double Star Catalog - http://ad.usno.navy.mil/wds/The Aladin Sky Atlas - http://aladin.u-strasbg.fr/aladin.gmlSloan Digital Sky Survey - http://cas.sdss.org/astro/en/tools/explore/Masa E. R., 2009 “CCD Double-Star MeasurementsatObservatorio Astronómico Camino de Palomares(OACP): First Series” , JDSO, 5, 18, 2009.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 32Divinus Lux Observatory Bulletin: Report #24Dave ArnoldProgram Manager for Double Star Research2728 North Fox Run DriveFlagstaff, AZ 86004Email: dvdarnl@gmail.comAbstract: This report contains theta/rho measurements from 109 different double star systems.The time period spans from 2010.616 to 2011.679. Measurements were obtained usinga 20-cm Schmidt-Cassegrain telescope and an illuminated reticle micrometer. This reportrepresents a portion of the work that is currently being conducted in double star astronomyat Divinus Lux Observatory in Flagstaff, Arizona.This article contains a listing of double starmeasurements that are part of a series, which havebeen continuously reported at Divinus Lux Observatory,since the spring of 2001. Beginning with thisarticle, the selected double star systems, which appearin the table below, have been taken exclusivelyfrom the 2006.5 version of the Washington DoubleStar Catalog (WDS), with published measurementsthat are no more recent than ten years ago. Thereare also some noteworthy items that are discussed,which pertain to a few of the measured systems.As in previous articles, this report contains somedouble stars with noteworthy theta/rho shifts becauseof the effects of proper motion by one or both ofthe components. To begin with, proper motion byboth component stars, for ES 1015 AB, has caused a4% rho value increase during the past decade. Likewise,proper motion by both components, for STF2944 AC, is responsible for a 4% rho value increase,but this occurred in just the last 5 years. Next,proper motion by the companion star, for GRV 440,caused a 2 degrees theta value decrease during thepast 10 years. A rho value decrease of 5% is beingreported for HJ 1927. Proper motion by both components,since 2001, is the cause for this shift.Two additional variances in the theta values fortwo more double stars are being noted. First, propermotion by the “A” component, for the BU 483 multiplestar system, appears to have caused significantincreases in the theta values for AC and AD duringthe past 10 years. Increases of over three degrees arebeing reported for both components. Secondly, thetheta value for STF 140 AC, which appears in thetable, is 2.5 degrees greater than the 1998 WDSvalue. Proper motion doesn’t appear to be the causein this case, but since this double star has few previousmeasurements, perhaps additional measurementswill help bring more accuracy to this parameter.In a similar context, the rho measurement inthis report, for HJ 3437, lines up more closely withthe listing for 1836 than it does for the one in 2002.Additional measures of this pair might also be usefulSome possible corrections are being suggested forthe 2006.5 version of the WDS catalog. First of all,the 2005 theta value for STF 3008 (23238-0828)might contain a typo, since the proper motion vectorsimply a theta value increase rather than a decrease.Based upon measurements for this report, it appears

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 33that this value might be 159 degrees instead of 150degrees. Secondly, the 2000 theta value for HJ 5547(22204+1102) reveals a 2 degrees increase from the1991 value, when the proper motion vectors suggestjust the opposite. The theta measurement appearingin this report seems to validate a decreasing thetavalue.Another unexplained discrepancy from catalogvalues pertains to STF 431 (03424+3358). The WDScatalog lists the parameters for this double star as249 degrees and 25.6” in 2001, but measurements ofthis pair on 2010.847 yielded theta/rho values of243.8 degrees and 19.75 seconds. Proper motion shiftsare not significant enough to account for this and noother pairs with similar parameters or magnitudesappear in this part of the sky. Perhaps other researchersmight consider measuring this double starDivinus Lux Observatory Bulletin: Report #24to either confirm the 2001 catalog values or the onesobtained for this report.In a similar context, the historical data in theWDS catalog seems to suggest a position angle increase,over time, for S 799AB (21434+3817) but theposition angle measurement obtained for this articleis more closely in line with the value listed for 1824.Again, others may want to consider making additionalposition angle measurements of this pair inorder to help verify the actual value.Finally, the rho measurement in the catalog forARY 9 (00116+5813), for 2002, appears to possibly bein error. The rho measurement in this report, for thisdouble star, is much more closely aligned with themeasurements in 1910, rather than the 2002 measurements.NAME RA DEC MAGS PA SEP DATE NOTESSTF2688 20308+1347 9.2 10.4 174.3 7.67 2010.616 1GRV 440 21157+2355 10.6 10.6 297.9 43.94 2010.616 2ES 1012 21467+5523 10.5 10.6 5.5 4.44 2010.616 3ES 1015AB 21584+5245 10.4 10.7 238.7 7.90 2010.616 4POP 145AB-CD 22042+4633 9.5 9.8 94.1 30.61 2010.616 5STT 465 AB 22120+5012 7.3 10.5 317.3 12.84 2010.616 6BU 477 22159+3125 9.5 10.3 40.8 6.42 2010.616 7HJ 5547 22204+1102 7.5 10.1 300.9 40.98 2010.616 8STF2944AC 22478-0414 7.2 8.5 87.1 60.24 2010.616 9STF3008 23238-0828 7.1 7.6 159.2 5.93 2010.616 10ARG 47 00027+5958 9.3 10.3 290.4 9.88 2010.638 11HJ 1927 00032+4508 9.1 10.1 73.4 9.88 2010.638 12BU 483AC 00091+4051 6.9 7.5 270.4 158.00 2010.734 13BU 483AD 00091+4051 6.9 10.4 275.3 227.13 2010.734 13HJ 1953AC 00194-0849 3.5 10.3 190.7 107.14 2010.638 14HJ 1981A-BC 00310-1005 6.9 8.4 88.1 78.51 2010.638 15STF 104 01170+3828 7.9 9.8 321.6 13.33 2010.638 16HDO 45 01172+0201 7.2 9.5 102.6 38.02 2010.638 17H 23AC 01201+5814 5.0 7.0 231.0 134.30 2010.638 18H 23AD 01201+5814 5.0 10.2 287.8 178.74 2010.638 18H 23AE 01201+5814 5.0 10.3 239.0 170.84 2010.638 18H 23CE 01201+5814 7.0 10.3 265.3 41.97 2010.638 18Table continues on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 34Divinus Lux Observatory Bulletin: Report #24NAME RA DEC MAGS PA SEP DATE NOTESWEI 3 01201+3639 8.9 9.7 188.4 4.94 2010.638 19S 398 01284+0758 6.2 8.0 99.5 69.13 2010.658 20HJ 2052 01316-1901 6.8 7.4 113.9 80.98 2010.658 21STF 135AB-C 01341+3612 8.0 10.5 260.4 7.90 2010.658 22STF 135AB-D 01341+3612 8.0 10.6 51.0 50.86 2010.658 22STT 33AB 01374+5838 7.3 8.8 77.1 26.66 2010.658 23DOB 2AC 01374+5838 7.3 10.2 109.3 106.65 2010.658 23STF 140AC 01390+4104 9.2 9.9 322.5 195.53 2010.734 24STF 150 01434-0705 7.7 8.2 195.8 36.04 2010.658 25ENG 8 01496-1041 4.7 6.7 250.4 183.68 2010.658 26STF 4AB 01562+3715 5.7 5.9 297.5 202.44 2010.658 27BU 1368Bb 01562+3715 5.9 9.6 258.2 204.41 2010.658 27STF 245Aa-B 02186+4017 7.2 8.0 293.9 11.36 2010.658 28STT 27AB 02268+1034 6.7 8.3 31.9 73.57 2010.658 29STF 431 03424+3358 5.0 10.0 243.8 19.75 2010.847 30WEB 4 05290-0442 9.8 10.0 232.9 47.89 2010.978 31STF 785AB 05459+2555 7.3 8.3 347.8 14.32 2010.978 32STT 116AD 05459+2555 7.3 10.2 10.5 201.45 2010.978 32BU 93AB 05489+2101 9.0 10.2 122.1 60.24 2010.978 33H 125AB 05506+5655 6.5 10.4 128.0 26.19 2010.978 34BRT1188 05596+1312 10.0 10.1 354.6 5.43 2010.978 35GUI 10AC 06117+1723 7.5 9.0 35.9 73.08 2010.978 36STF 889AB 06199+2501 7.4 9.9 243.2 21.23 2010.978 37WAL 43AC 06199+2501 7.4 10.1 322.2 38.51 2010.978 37A 2720AC 06234+1432 9.3 9.6 28.6 67.15 2010.978 38STF1174AB-C 08047+4717 8.9 9.3 215.0 5.93 2011.118 39WFC 81 09133+0540 10.2 10.4 76.5 8.39 2011.118 40A 2367AB 10100+1623 9.9 10.6 85.0 60.74 2011.118 41STF1435 10280+1950 10.3 10.7 203.2 8.89 2011.173 42STF1442 10320+2202 8.2 8.5 156.8 13.33 2011.118 43STF1447 10338+2321 7.5 8.8 124.4 4.44 2011.118 44BU 111AC 10512-0906 10.0 9.4* 130.7 64.19 2011.173 45STF3072 11309-0643 7.7 9.9 331.1 9.88 2011.173 46ES 626 15409+5009 9.2 9.2 275.1 7.90 2011.367 47STF 29AB 16224+3348 5.2 5.4 164.2 356.49 2011.367 48Table continues on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 35Divinus Lux Observatory Bulletin: Report #24NAME RA DEC MAGS PA SEP DATE NOTESWEB 6 16354+1703 6.4 7.3 359.2 157.01 2011.411 49STF 32AC 16579+4722 7.8 7.9 259.9 111.59 2011.367 50STF 2156 17240-0050 9.0 9.4 35.0 3.95 2011.411 51AG 210 17378+2257 9.9 10.2 187.5 4.44 2011.367 52H 50AC 18497-0555 6.0 8.1 171.2 110.60 2011.411 53STT 178 19153+1505 5.6 7.6 268.2 89.86 2011.501 54STF 40AB 19188+0020 6.4 6.7 316.6 426.60 2011.501 55STF 2498AB 19202+0403 8.1 8.8 66.1 11.85 2011.501 56BOT 2AC 19202+0403 8.1 10.1 101.2 171.83 2011.501 56STT 182AB 19268+5009 7.4 8.6 297.5 73.08 2011.501 57HU 342 19371+1723 9.7 10.3 254.3 4.44 2011.501 58STF 45AB 19431-0818 7.1 7.5 146.9 97.76 2011.501 59ARY 23AB 20133+3502 8.4 8.8 28.3 80.98 2011.559 60ARY 23BC 20133+3502 8.4 10.5 339.8 65.18 2011.559 60ARY 1 20198+3707 6.6 8.5 257.3 77.03 2011.559 61SHJ 323AD 20289-1749 4.9 6.6 149.8 258.73 2011.559 62S 752AC 20302+1925 6.8 7.3 288.0 106.65 2011.559 63ES 667 20386+4438 9.7 10.3 184.9 9.88 2011.556 64STT 533AC 20391+1005 5.1 8.5 100.2 212.31 2011.556 65STF 54AD 21103+1008 4.7 6.1 151.7 335.75 2011.559 66STF 2780Aa-C 21118+5959 6.1 8.9 210.7 120.48 2011.559 67WAL 137AB-E 21118+5959 6.1 10.3 44.5 61.72 2011.559 67STF 55AB 21238+3721 6.4 6.6 303.0 362.41 2011.556 68S 799AB 21434+3817 5.7 7.0 58.9 149.11 2011.556 69S 799AC 21434+3817 5.7 10.1 318.1 135.29 2011.556 69STF 2822AD 21441+2845 4.7 6.9 43.8 197.50 2011.559 70HWE 59AB 22015-1537 7.1 10.2 270.1 8.89 2011.559 71HJ 5524AD 22015-1537 7.1 9.9 312.8 180.71 2011.559 71HJ 5355AB 22386-1404 7.5 8.7 289.3 83.44 2011.559 72HJ 5355AC 22386-1404 7.5 9.2 359.3 106.65 2011.559 72BU 1144Aa-BC 22430+3013 2.9 9.8 338.0 93.32 2011.559 73STF 59AB-C 23052-0742 5.4 7.1 149.6 253.79 2011.674 74S 823AC 23097+5920 5.7 8.2 162.8 166.89 2011.674 75STF 2991 23134+1104 5.9 10.0 358.8 33.08 2011.674 76ES 2725AB 23191+4855 7.2 8.5 235.0 54.31 2011.674 77Table concludes on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 36Divinus Lux Observatory Bulletin: Report #24NAME RA DEC MAGS PA SEP DATE NOTESHJ 5413AB 23418-1749 4.8 8.5 4.2 118.50 2011.674 78STF3054 00031+0816 8.1 9.0 181.3 33.58 2011.677 79HJ 1929AB-C 00039+2759 8.7 9.5 287.3 5.43 2011.677 80ARY 7AB 00104+5831 7.7 8.3 2.7 124.43 2011.677 81ARY 8AB 00108+5846 8.1 8.6 100.4 39.01 2011.677 82ARY 8AC 00108+5846 8.1 8.3 42.8 104.68 2011.677 82ES 2577 00112+4933 8.2 8.9 310.9 66.16 2011.677 83ARY 9 00116+5813 7.1 8.5 82.7 138.30 2011.677 84STF 8 00116-0305 7.8 9.2 291.1 7.90 2011.677 85STF 17AB 00165+2918 8.3 9.8 29.6 27.16 2011.677 86STF 28 00239+2930 8.3 8.5 224.0 33.08 2011.677 87STT 10AB 00275+1602 6.4 10.1 239.9 113.56 2011.677 88STT 10AC 00275+1602 6.4 9.3 156.0 274.53 2011.677 88STF 49 00408-0714 7.0 9.8 321.5 8.72 2011.677 89ES 224AC 00473+3837 9.4 10.4 108.6 66.66 2011.677 90STF 70AB 00538+5242 6.3 9.4 247.2 8.39 2011.677 91STF 72 00546+3910 8.2 9.1 173.3 23.70 2011.677 92S 390 00582-1541 7.7 7.8 215.5 6.42 2011.677 93BU 234AB 01005-1705 9.1 9.2 333.3 4.94 2011.679 94BU 234AC 01005-1705 9.1 9.1 129.0 62.21 2011.679 94HJ 2010 01027+4742 8.3 9.6 270.7 9.88 2011.679 95STT 23AB 01101+5145 8.1 8.5 190.9 14.32 2011.679 96ENG 4AB 01107+4256 7.7 9.9 308.4 152.08 2011.679 97HJ 2030AC 01170+5345 8.6 9.1 193.1 38.51 2011.679 98AG 17 01208+1127 8.3 10.3 98.5 54.81 2011.679 99ES 1712AB 01243+5858 7.7 9.3 2.3 47.40 2011.679 100ES 2583 01246+5311 8.2 9.1 344.6 26.17 2011.679 101STT 30AC 01256+3133 8.0 8.0 105.7 56.78 2011.679 102HJ 3437 01281-1716 7.4 9.3 247.3 12.34 2011.679 103ARN 32AE 01433+6033 5.8 7.0 267.9 316.99 2011.679 104HJ 644AC 01487+0741 7.1 9.7 226.2 128.38 2011.679 105BUP 26Aa-B 01515-1020 3.7 10.0 40.1 188.61 2011.679 106FRK 2 01564+3026 7.9 9.1 306.6 53.82 2011.679 107A 819AB-C 01570+3101 7.7 9.9 271.2 66.66 2011.679 108BU 7AC 01580-0204 6.6 8.8 199.0 152.08 2011.679 109

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 37Divinus Lux Observatory Bulletin: Report #24Notes1. In Delphinus. Sep. & p.a. increasing. Spect.G0.2. In Vulpecula. Position angle decreasing.3. In Cygnus. Relatively fixed.4. In Cygnus. Separation increasing; positionangle decreasing.5. In Lacerta. Separation slightly increasing.6. Sep. & p.a. decreasing. Spect. F0II.7. In Pegasus. Position angle decreasing. Spect.F5, F5.8. In Pegasus. Sep. increasing; p.a. decreasing.Spect. K0.9. In Aquarius. Sep. increasing; p.a. decreasing.Spect. G2V, F5.10. Sep. and p.a. increasing. Spect. K0III, K0.11. In Cassiopeia. Position angle slightly increasing.Spect. K, A0.12. In Andromeda. Sep. & p.a. decreasing. Spect.F8, F5.13. In Andromeda. AC & AD = sep. & p.a. increasing.Spect. A & C = G5, G5.14. 8 Ceti. Position angle decreasing. Spect. K0.15. In Cetus. Position angle slightly increasing.Spect. A5IV, G1V.16. In Andromeda. Relatively fixed. Spect. G5.17. In Cetus. Sep. & p.a. increasing. Spect. G5.18. Phi or 34 Cassiopeiae. All components relativelyfixed. Spect. AC = F5, B5.19. In Andromeda. Common proper motion; sep.& p.a. inc. Spect. G0, G0.20. In Pisces. Relatively fixed. Common propermotion. Spect. K1III, G0.21. In Cetus. Sep. increasing; p.a. decreasing.Spect. A7III, K0.22. In Andromeda. AB-C=fix.; c.p.m. AB-D=sep.& p.a. dec. Spect. AB-C= A2.23. In Cassiopeia. AB = sep. & p.a. inc. AC = relfix.Spect. AB = B3IV, K7.24. In Andromeda. Separation increasing. Spect.F2V, K0.25. In Cetus. Relatively fixed. Common propermotion. Spect. A, A.26. Chi or 53 Ceti. Relatively fixed. Commonproper motion. Spect. F3III.27. 56 Andromedae. AB = sep inc.; p.a. dec. Bb =relfixed. Spect. K0III, M0.28. In Andromeda. Common proper motion. Sep.& p.a. slightly inc. F3V, F3V.29. In Aries. Relatively fixed. Common propermotion. Spect. A3, F0.30. In Perseus. Position angle increasing. Spect.B1.5IV.31. In Orion. Position angle increasing. Spect. M7,M.32. In Taurus. AB = sep. slightly increasing. AD =relatively fixed. Spect. B9.33. In Taurus. Common proper motion; p.a.slightly decreasing. Spect. A0, G5.34. In Camelopardus. Sep. increasing; p.a. decreasing.Spect. A4IV.35. In Orion. Common proper motion; p.a.slightly decreasing.36. In Orion. Sep. decreasing; p.a. increasing.Spect. B9.5III, F8.37. In Gemini. AB = p.a. increasing. AC = sep. &p.a. increasing. Spect. K2.38. In Orion. Position angle decreasing. Spect.F7V.39. In Lynx. Relatively fixed. Common proper motion.Spect. F5, F5.40. In Hydra. Common proper motion. Sep. & p.a.slightly increasing. Spect. G5.41. In Leo. Common proper motion. Sep. slightlydecreasing. Spect. G0, G5.42. In Leo. Sep. & p.a. increasing. Spect. G0, G.43. In Leo. Separation decreasing. Spect. F0, A.44. In Leo. Common proper motion; p.a. slightlyincreasing. Spect. A2, A2.45. In Sextans. Separation decreasing. Spect. of C= F2.46. In Crater. Relatively fixed. Common propermotion. Spect. F6V, F8.47. In Bootes. Separation decreasing.48. Nu Coronae Borealis. Separation decreasing.Spect. M2III, K5.49. In Hercules. Relatively fixed. Common propermotion. Spect. A2V, A5.50. In Hercules. Relatively fixed. Common propermotion. Spect. K8, K8.51. In Ophiuchus. Common proper motion; p.a.increasing. Spect. F2, F2.52. In Hercules. Common proper motion; p.a. increasing.Spect. M0V, M0.53. In Scutum. Position angle increasing. Spect.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 38Divinus Lux Observatory Bulletin: Report #24K1II, K0.54. In Aquila. Relatively fixed. Common propermotion. Spect. G8II, A0.55. In Aquila. Separation slightly increasing.Spect. K0III, F0.56. In Aquila. AB = relfix; c.p.m. AC = relfix.Spect. AB = G5II, K.57. In Cygnus. Sep. increasing; p.a. decreasing.Spect. F6V, A5.58. In Sagitta. Sep. & p.a. increasing. Spect. F8.59. In Aquila. Relatively fixed. Common propermotion. Spect. F4V, F5V.60. In Cygnus. AB = sep. inc. BC = p.a. dec.Spect. AB = B0, F8.61. In Cygnus. Separation increasing. Spect. A0,K0.62. Rho or 11 Capricorni. Separation increasing.Spect. F3V, K0.63. In Delphinus. Relatively fixed. Commonproper motion. Spect. B7IV, B9.64. In Cygnus. Relatively fixed. Spect. K0.65. Kappa or 7 Delphini. Relfixed. Commonproper motion. Spect. G1, K0.66. Gamma or 5 Equulei. Sep. & p.a. decreasing.Spect. A9V, A2.67. In Cepheus. Aa-C & AB-E = p.a. slightly decreasing.Spect. B0II, B3, A0.68. In Cygnus. Separation decreasing. Spect. K5,F8.69. 79 Cygni. AB = sep. decreasing. AC = sep.increasing. Spect. AB = A0V, A0.70. Mu or 1 Cygni. Sep. & p.a. decreasing. Spect.F7V, A5.71. In Aquarius. AB = relfix, cpm. AD = sep. inc;p.a. dec. Spect. AB = G8, G8.72. In Aquarius. AB = sep. inc.; p.a. dec. AC =p.a. dec. Spect. A5II, F6V, M7.73. Eta or 44 Pegasi. Separation increasing. Spect.G0, G5.74. 83 Aquarii. Sep. decreasing; p.a. increasing.Spect. A9III, K0.75. 2 Cassiopeiae. Relatively fixed. Spect. A5III,B8.76. In Pegasus. Sep. & p.a. slightly decreasing.Spect. G8III, G8III.77. In Andromeda. Sep. & p.a. increasing. Spect.A2, G5.78. 104 Aquarii. Sep. & p.a. decreasing. Spect.G0I, F.79. In Pisces. Relatively fixed. Common propermotion. Spect. F0, F0.80. In Pegasus. Sep. increasing; p.a. decreasing.Spect. F8.81. In Cassiopeia. Sep. & p.a. increasing. Spect. F,A5.82. In Cassiopeia. AB = relfix, c.p.m. AC = relfix.Spect. B5, B9, B8.83. In Cassiopeia. Relatively fixed. Commonproper motion. Spect. A2, F0.84. In Cassiopeia. Separation increasing. Spect.B5, G5.85. In Pisces. Relatively fixed. Common propermotion. Spect. F8, F8.86. In Andromeda. Separation increasing. Spect.K0, A.87. In Andromeda. Relatively fixed. Commonproper motion. Spect. G0, G0.88. In Pisces. AB = sep. inc. AC = p.a.inc. Spect.A5, F8, K2.89. In Cetus. Sep. increasing; common propermotion. Spect. G0, G0.90. In Andromeda. Separation increasing. Spect.A5.91. In Cassiopeia. Common proper motion; p.a.increasing. Spect. A0, A5.92. In Andromeda. Position angle decreasing.Spect. M.93. In Cetus. Common proper motion; p.a. increasing.Spect. F5, F5.94. In Cetus. AB = sep. & p.a. inc. AC = sep. inc.,p.a. dec. Spect. F0, F0, F0.95. In Andromeda. Relatively fixed. Commonproper motion. Spect. A0, A0.96. In Cassiopeia. Relatively fixed. Commonproper motion. Spect. F8, F8.97. In Andromeda. Position angle increasing.Spect. K0.98. In Cassiopeia. Relatively fixed. Spect. F2, A.99. In Pisces. Relatively fixed. Common propermotion. Spect. F8, K0.100. In Cassiopeia. Sep. & p.a. decreasing. Spect.K0.101. In Cassiopeia. Sep. decreasing; p.a. increasing.Spect. K2, K2.102. In Pisces. Relatively fixed. Common proper

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 39Divinus Lux Observatory Bulletin: Report #24motion. Spect. F8, G0.103. In Cetus. Relatively fixed. Common propermotion. Spect. F0.104. 44 Cassiopeiae. Relatively fixed. Spect. B9,K2.105. In Pisces. Separation slightly increasing.Spect. K0.106. Zeta or 55 Ceti. Position angle decreasing.Spect. K0, K0.107. In Triangulum. Common proper motion; sep.slightly inc. Spect. F0, F0.108. In Triangulum. Relatively fixed. Commonproper motion. Spect. F5, G0.109. In Cetus. Sep. & p.a. slightly increasing.Spect. A0, A0.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 40Astrometric Measurements of Seven DoubleStars, September 2011 ReportJoseph M. CarroCuesta CollegeSan Luis Obispo, CaliforniaAbstract: From my residence in Paso Robles, California, measurements of the separationand position angle of seven double stars were made. Listed in chronological order, the doublestars were Zeta Ursae Majoris, Zeta Lyrae, Epsilon Delphini, SAO 105104 in Sagitta,STF 2840 in Cepheus, 61 Cygni, and 17 Cygni. The two goals of this project were to measurethe position angle and separation of the aforementioned double stars, and to learn thenecessary techniques to conduct this research.MethodologyMy observations were made from my home inPaso Robles, California (located at approximately35 o 37’36” N and 120 o 41’24” W) using a Celestronmodel CPC 1100 telescope (Figure 1). The telescopeis computerized, motorized, and was fitted with aCelestron Micro Guide 12.5 mm astrometric eyepiece.The telescope is of Schmidt-Cassegrain design,with aperture of 11 inches on an alt-azimuthmount. The manufacturer reports a focal length of2,800 mm.The Micro Guide eyepiece was oriented with thecelestial coordinate system using the primary star ofthe double star under study. The primary star waspositioned on the mark 30, the drive was disabled,and the star was permitted to drift to the outer circle.The scale was rotated until the star lay on the270 degree mark. The accuracy of this setting wasverified by positioning the primary star on the 90degree mark of the outer circular scale, and allowingthe star to drift to the 270 degree mark.Following the orientation, drift times were measuredby placing the primary star on the 0 mark ofthe linear scale, and measuring the drift time fromthe 0 to the 60 mark using a stop watch precise to±0.01 seconds. Measurements were made, and theaverage drift time was calculated. That average wasused to calculate the scale constant Z, using the formula14 :Figure 1: The author with his Celestron telescope

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 41Astrometric Measurements of Seven Double Stars, September 2011 Report15.0411T ave cosδZ =Dwhere Tave is the average time, δ is the declinationangle, and D is the number of reticle divisions.Separation measurements were made by placingthe pair of stars on the linear scale at the zero mark,and then counting the number of scale divisions betweenthe stars. Because the scale has 60 divisions, itwas only possible to estimate to the nearest ¼ division.After each measurement, the double star wasrepositioned to the next major division. Measurementswere made, and an average and standard deviationwere calculated.The position angle measurements were made byaligning both stars on the linear scale with the primarystar at the 30 division and pointing to the 60mark, disabling the tracking feature, and then allowingthe stars to drift to the circular scales. The crossingof the primary star at the outer scale was approximatedto the nearest degree as the scale has divisionsof 5 o . Following each measurement, the tracking featurewas enabled and the process was repeated.Zeta Ursae Majoris - IntroductionThis double star is located in the constellation ofUrsa Major (the Great Bear), and is known by its traditionalname of Mizar with alternate spellings ofMirzar, Mizat, and Mirza. This double star has beenknown since ancient times, and was the first doublestar. On clear nights, the double star can be seenwithout the use of instruments. It was studied byBenedetto Castelli in 1617, and has been studied frequentlysince that time. Both stars are yellow withmagnitudes of 2.0 and 4.0 22 . The colors reported forthis pair vary considerably having been reported asboth white, white and emerald, both green, blue, oryellow. For the AB components, Right Ascension is13 h 23 m 56 s and the Declination is +54 o 55’31”. Whatwas once thought to be a double star is actually acomplex of six stars which are all gravitationallybound 20 .The catalog identifiers for this double star include79 Ursae Majoris, ADS 8891AB, BD+55 1598A, BGC18133, FK5 497, HD 116656, HIP 65378, HR 5054,SAO 28737, STF 1744, and WDS 13239+5456. Itsprecise coordinates are 132355.42+545531.5. 22Table 1: Literature Search; Separation (arc seconds);Position angle (degrees) for Zeta Ursae MajorisReference name Sep PAWilliam Herschel Catalog 1779 data 19 14.3 153Washington Double Star Cat. 35 1993 data 14.5 152Eagle Creek Observatory 24 14.4 151Daley, 2009 37 14.3 152.5Measurements by the author 2011 14.7 152.3Zeta Ursae Majoris - ObservationsThe measurements were made on 11 May 2011(Bessell date 2011.359) beginning at 9:50pm and endingat 11:50pm Pacific Daylight Time. The night wasclear and calm, and there was a ½ moon. The temperatureranged from 60 to 50 o F. There was a breezeof 5 – 10mph which affected the telescope and severalmeasurements were repeated.The linear scale of the Micro Guide eyepiece wasoriented with the celestial coordinate system usingthe primary star. Once the orientation was completed,12 drift time measurements were made, withan average value of 47.19 seconds, a standard deviationof 0.63 seconds, and a standard error of the meanof 0.18 seconds. The result was a scale constant of 6.8arc seconds per division.The primary star was placed on the linear scale,and 12 separation measurements were taken. Theaverage value was 2.2 divisions with a standard deviationof 0.22 divisions, and a standard error of themean of 0.06 divisions. When adjusted for significantfigures, the calculated separation was 14.7 arc seconds.The position angle measurements were made usingthe aforementioned methodology, and 18 positionangle measurements were taken with an averagevalue of 152.3 o , a standard deviation of 1.5 o , and astandard error of the mean of 0.27 o .The separation value of 14.7 arc seconds and positionangle value of 152.3 o compared well with theseparation value of 14.5 arc seconds and the positionangle value of 152 o published in the Washington DoubleStar catalog. 35 See Table 1.Zeta Lyrae – IntroductionLocated in the constellation of Lyra (the Harp),the double star Zeta Lyrae has been known since ancienttimes. Its right ascension is 18 h 44 m 46 s and itsdeclination is +37 o 36’18”. The yellow primary andblue-white secondary stars have magnitudes of 4.4and 5.7 respectively. Modern observations have

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 42Astrometric Measurements of Seven Double Stars, September 2011 Reportshown that Zeta Lyrae is a spectroscopic binary(Wikipedia).The catalog identifiers for this pair include 6 Lyrae,BD+37 3222, BU 968, CSV 101763, GSC03118+02080, HD 173648, HIP 91971, HR 7056, PPM81740, SAO 67321, STF 38, UBV 15954, and WDS18448+3736. Its precise coordinates are184446.34+373618.2. 22Zeta Lyrae – ObservationsThe measurements were made on 11 July 2011(Bessell date 2011.526) beginning at 10:15pm andending at 11:50pm Pacific Daylight Time. The nightwas clear, and the moon was gibbous. The temperatureranged from 60 to 50 o F. The wind was gentle at1 – 5mph.The linear scale of the Micro Guide eyepiece wasoriented with the celestial coordinate system usingthe primary star. Once the orientation was completed,12 drift time measurements were made, withan average value of 35.94 seconds, a standard deviationof 0.29 seconds, and a standard error of the meanof 0.08 seconds. The result was a scale constant of7.13 arc seconds per division.The primary star was placed on the linear scale,and 12 separation measurements were taken. Theaverage value was 6.17 divisions with a standard deviationof 0.25 divisions, and a standard error of themean of 0.07 divisions. When adjusted for significantfigures, the calculated separation was 44.0 arc seconds.The position angle measurements were made usingthe aforementioned methodology, and 18 positionangle measurements were taken with an averagevalue of 149.9 o , a standard deviation of 2.18 o , and astandard error of the mean of 0.4 o .The separation value of 44.0 arc seconds and positionangle value of 149.9 o compared well with theseparation value of 43.7 arc seconds and the positionangle value of 150 o published in the Washington DoubleStar catalog 22 . See Table 2.Epsilon Delphini - IntroductionLocated in the constellation of Delphinus (the Dolphin),the double star Epsilon Delphini consists of apair of yellow-white stars of magnitudes 7.1 and 7.4.For the AB components, the right ascension is20 h 31 m 12 s and its declination is +11 o 15’34” 22 . It doesnot have a traditional name.The catalog identifiers for this pair include ADS13946BC, AG+11 2505, BD+10 4307B, CSI+10 43071, GC 28544, GCRV 12819, GEN+1.00195482, HDTable 2 Literature Review: Separation (arc seconds) andPosition angle (degrees) for Zeta LyraeReference name Sep PAWashington Double Star Cat. 35 1835 data 43.7 150Bright Star Catalog 17 43.7 -Burton, 2006 10 43.6 150Perez, 2005 27 43.7 150Arnold, 2008 6 43.9 149.8Bell, 2011 9 44 150Schlimmer 33 2009 data 43.4 150.4Washington Double Star Cat. 22 2010 data 43.7 150Measurements by the author 2011 44.0 149.8195482, HIP 101233, IDS 20264+1055, PPM 138507,SAO 106195, SKY 38830, STF 2690, UBV M24917,and WDS J20312+1116BC. Its precise coordinatesare 203111.94+111533.7. 22Epsilon Delphini – ObservationsThe measurements were made on 1 August 2011(Bessell date 2011.584) beginning at 9:30pm and endingat 11:00pm Pacific Daylight Time. The night wasclear, with no moon. The temperature range wasfrom 65 to 55 o F. There was a 0 – 5mph breeze, andthe humidity was 25%.The linear scale of the Micro Guide eyepiece wasoriented with the celestial coordinate system usingthe primary star. Once the orientation was completed,12 drift time measurements were made, withan average value of 28.91 seconds, a standard deviationof 0.28 seconds, and a standard error of the meanof 0.08 seconds. The result was a scale constant of7.11 arc seconds per division.The primary star was placed on the linear scale,and 12 separation measurements were taken. Theaverage value was 2.5 divisions with a standard deviationof 0.0 divisions, and a standard error of themean of 0.0 divisions. When adjusted for significantfigures, the calculated separation was 17.7 arc seconds.The position angle measurements were made usingthe aforementioned methodology, and 18 positionangle measurements were taken with an averagevalue of 256 o , a standard deviation of 1.5 o , and a standarderror of the mean of 0.28 o .The separation value of 17.7 arc seconds and theposition angle of 256 o compared well with the values

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 43Astrometric Measurements of Seven Double Stars, September 2011 ReportTable 3: Literature Review, Separation (arc seconds)and Position angle (degrees) for Epsilon DelphiniReference name Sep PAWashington Double Star Cat. 22 1777 data 15.0 281The Hipparcos Catalog 28 1997 data 16.7 253Eagle Creek Observatory 24 16.7 256Arnold, 2006 5 17.8 254.8Schlimmer, 2007 30 17.3 254.1Schlimmer, 2009 32 17.7 254.8Washington Double Star Cat. 22 2009 data 17.3 255Table 4: Literature Review, Separation (arc seconds);Position angle (in o ) for SAO 105104 in SagittaReference name Sep PAW. Herschel (McEvoy 2011) 19 1796 data 28.2 302Hipparcos Catalog 28 30.0 301.2SKY2000 Master Catalog 25 28.2 302C C D M Catalog 13 28.2 302Arnold 2010 8 28.6 301.3Washington Double Star Cat. 22 2010 data 28.6 301Measurements by the author 2011 29.0 301Schlimmer 2010 33 17.3 255.1The Tycho Catalog 15 17.4 254.8Measurements by the author 2011 17.7 255.9of 17.3 and 255 o as given in the Washington DoubleStar catalog 22 . See Table 3.SAO 105104 in Sagitta – IntroductionLocated in the constellation of Sagitta (the Arrow)is this double star of which the primary star is yelloworangeand the secondary star is white. With magnitudesof 6.4 and 9.5, the secondary star approachedthe limit of the CPC 1100 telescope. Its Right Ascensionis 19 h 39 m 25 s and its Declination is +16 o 34’16” 22 .This double star has no traditional name.The catalog identifiers includeAG+16 2018,BC+16 3936, GSC 01602-01582, HD 185622, JIP96688, HP 7475, IRAS 19371+1627, PPM 136711,SAO 105104, TYC 1602-1582-1, V 0340, and WDS1934+1634A. Its precise coordinates are193925.33+163416.0. 22SAO 105104 in Sagitta – ObservationsThese measurements were made on 3 August2011 (Bessell date 2011.589) beginning at 9:30pm andending at 11:00pm Pacific Daylight Time. The nightwas clear, with a ¼ moon in the southwest. The temperaturerange was from 65 to 55 o F. There was a 0 –5mph breeze. The humidity was 30%.The linear scale of the Micro Guide eyepiece wasoriented with the celestial coordinate system usingthe primary star. Once the orientation was completed,12 drift time measurements were made, withan average value of 30.36 seconds, a standard deviationof 0.15 seconds, and a standard error of the meanof 0.04 seconds. The result was a scale constant of 7.3arc seconds per division.The primary star was placed on the linear scale,and 12 separation measurements were taken. Theaverage value was 4.0 divisions with a standard deviationof 0.0 divisions, and a standard error of themean of 0.0 divisions. When adjusted for significantfigures, the calculated separation was 29.0 arc seconds.The position angle measurements were made usingthe aforementioned methodology, and 18 positionangle measurements were taken with an averagevalue of 301 o , a standard deviation of 1.7 o , and a standarderror of the mean of 0.31 o .The separation value of 29.0 arc seconds and positionangle value of 301 o compared well with the separationvalue of 28.6 arc seconds and the position anglevalue of 301 o published in the Washington DoubleStar Catalog 22 . See Table 4.STF 2840 in Cepheus – IntroductionLocated in the constellation of Cepheus, this pairof yellow stars has magnitudes of 5.6 and 6.4. STF2840 in Cepheus has been well studied, but little hasbeen written about this pair. The WDS gives itsRight Ascension is 21 h 52 m 01 s and its Declination is+55 o 47’48” 22 , however, the Cambridge Double StarAtlas lists an R.A. of 21 h 52 m 19 s and a Dec. of+55 o 50’10”, and the data from the Hipparcos Catalog 28is an R.A. of. 21 h 52 m 00 s and a Dec. of +55 o 47’31”.The catalog identifiers include ADS 15045, AG+551503, BD+55 2638, HD 208063, HIP 107929, IDS21486+5519B, PPM 39938, SAO 33817, SKY 41670,TYC 3972-2737-1, UBV 187420, and WDS21520+5548B. Its precise coordinates are215201.02+554748.3 22

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 44Astrometric Measurements of Seven Double Stars, September 2011 ReportTable 5: Literature Review: Separation (arc seconds); Positionangle (degrees) for STF 2840 in CepheusReference name Sep PAWashington Double Star Cat. 22 1782 data 21.2 192Hipparcos Catalog 28 1993 data 17.9 197Eagle Creek Observatory 24 18.3 196Arnold 2010 8 17.8 196.8Washington Double Star Cat. 22 2010 data 17.8 197Measurements by the author 2011 18.1 196Table 6: Literature Review, Separation (arc seconds) and Positionangle (degrees) for 61 CygniReference name Sep PAW. Herschel (MacEvoy 2011) 19 1753data35 19.6Bright Star Cat. 17 28.7 -Washington Double Star Cat. 351993 data30.4 149The Hipparchos Catalog 28 1993data 22 31.6 151.2Arnold 2006 4 2004 data 31.1 150.9Muller 2007 23 2005 data 31.6 152.6STF 2840 in Cepheus – ObservationsThe measurements were made on 9 August 2011(Bessell date 2011.605) beginning at 10:20 pm andending at 11:30 pm Pacific Daylight Time. The nightwas clear, calm, with a gentle breeze of 1 – 5 mph.The moon was 2/3 full in the southwest. The temperatureranged from 60 to 50 o F. The humidity was65%, and seeing was 3 - 4.The linear scale of the Micro Guide eyepiece wasoriented with the celestial coordinate system usingthe primary star. Once the orientation was completed,12 drift time measurements were made, withan average value of 51.55 seconds, a standard deviationof 0.25 seconds, and a standard error of the meanof 0.08 seconds. The result was a scale constant of 7.3arc seconds per division.The primary star was placed on the linear scale,and 12 separation measurements were taken. Theaverage value was 2.5 divisions with a standard deviationof 0.0 divisions, and a standard error of themean of 0.0 divisions. When adjusted for significantfigures, the calculated separation was 18.1 arc seconds.The position angle measurements were made usingthe aforementioned methodology, and 18 positionangle measurements were taken with an averagevalue of 196 o , a standard deviation of 1.3 o , and a standarderror of the mean of 0.24 o .The separation value of 18.1 arc seconds and positionangle value of 196 o compared well with the separationvalue of 17.8 arc seconds and the position anglevalue of 197 o published in the Washington DoubleStar catalog 22 . See Table 5.61 Cygni – IntroductionLocated in the constellation of Cygnus (the Swan)is 61 Cygni, a famous pair of orange stars. First studiedPiazzi in 1792, the pair has a large proper motionPerez 2006 27 36 140Schlimmer 2009 31 2008 data 31.0 151.3Heijen 2008 16 31.1 151Anton 2011 2 Oct 9 31.2 151.3Anton 2011 2 Oct 12 31.35 151.6Washington Double Star Cat. 222010 data31.4 152Measurements by the author 2011 31.9 151of about 5 arc seconds per year, and is sometimescalled the “Flying Star” 39 . In 1838 Bessell measuredthe parallax and distance from the Earth for this pair,which was the first double star to be so measured 38 .The orange pair is distinct, but the surroundings lackany prominent stars. The pair has magnitudes of 5.2and 6.1. Its Right Ascension is 21 h 06 m 54 s and itsDeclination is +38 o 44’ 58” 22 .The catalog identifiers include BD+38 4343, FK5793, HD 201091, HIP 104214, HR 8085, GC 29509,GJ 820, PPM 86045, SAO 70919, STF 2758, UBV18287, and WDS 21069+3845. Its precise coordinatesare 210653.94+384457.8. 2261 Cygni – ObservationsThe measurements were made on 14 August 2011(Bessell date 2011.619) beginning at 8:45pm and endingat 9:30pm Pacific Daylight Time. The night wasclear and calm with no moon. The temperatureranged from 75 to 65 o F. The humidity was 25%, andseeing at 4 – 5. The wind at 5 - 10mph affected themeasurements, and many were repeated.The linear scale of the Micro Guide eyepiece wasoriented with the celestial coordinate system usingthe primary star. Once the orientation was completed,12 drift time measurements were made, withan average value of 36.17 seconds, a standard devia-

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 45Astrometric Measurements of Seven Double Stars, September 2011 ReportTable 7: Literature Review, Separation (arc seconds)17 Cygni – Observationsand Position angle (degrees) for 17 CygniReference name Sep PAW. Herschel (MacEvoy 2011) 19 1822 data 25.5 73Starland Catalog (Olcott 1909) 26 26.2 69Washington Double Star Cat. 35 1993 data 26.3 69Hipparcos Catalog 28 26.2 67.5Eagle Creek Observatory 24 26 70Astrogeek (Burton 2011) 10 2006 data 26.3 67Arnold 2010 7 26.2 69Washington Double Star Cat. 22 2009 data 26.2 69Measurements by the author 2011 25.5 69tion of 0.37 seconds, and a standard error of the meanof 0.09 seconds. The result was a scale constant of7.07 arc seconds per division.The primary star was placed on the linear scale,and 12 separation measurements were taken. Theaverage value was 4.5 divisions with a standard deviationof 0.1 divisions, and a standard error of themean of 0.03 divisions. When adjusted for significantfigures, the calculated separation was 31.9 arc seconds.The position angle measurements were made usingthe aforementioned methodology, and 18 positionangle measurements were taken with an averagevalue of 150.8 o , a standard deviation of 1.3 o , and astandard error of the mean of 0.31 o .The separation value of 31.9 arc seconds and theposition angle value of 151 degrees compared favorablywith the values of 31.4 arc seconds and 152 degreesas published in the Washington Double StarCatalog (Mason+ 2011) 22 . See Table 6.References17 Cygni – IntroductionLocated in the constellation of Cygnus (the Swan),17 Cygni is a yellow pair of stars with magnitudes of5.1 and 9.3. Its right ascension is 19 h 46 m 26 s and itsdeclination is +33 o 43’ 39”. 22The catalog identifiers include ADS 12913A,BD+33 3587, CSI+33 3587 1, GC 27369, HD 187013,HIP 97295, HR 7534, PLX 4654, PPM 83516, SAO68827, STF 2580AB, TYC 2660-4227-1, and WDS19464+3344. Its precise coordinates are194625.60+334339.3. 22The measurements were made on 15 August 2011(Bessell date 2011.622) beginning at 8:30 pm and endingat 10:30 pm Pacific Daylight Time. The night wasclear with moonrise at 9:30pm. The temperatureranged from 75 to 65 o F. The wind was 1 - 5mph, humidity30%, and seeing 3 – 4.The linear scale of the Micro Guide eyepiece wasoriented with the celestial coordinate system usingthe primary star. Once the orientation was completed,12 drift time measurements were made, withan average value of 33.84 seconds, a standard deviationof 0.2 seconds, and a standard error of the meanof 0.06 seconds. The result was a scale constant of 7.1arc seconds per division.The primary star was placed on the linear scale,and 12 separation measurements were taken. Theaverage value was 3.6 divisions with a standard deviationof 0.10 divisions, and a standard error of themean of 0.03 divisions. When adjusted for significantfigures, the calculated separation was 25.5 arc seconds.The position angle measurements were made usingthe aforementioned methodology, and 18 positionangle measurements were taken with an averagevalue of 68.9 o , a standard deviation of 1.35 o , and astandard error of the mean of 0.25 o .The separation value of 25.5 arc seconds and theposition angle value of 69 degrees compared well withthe values of 26 arc seconds and 69 degrees from theWashington Double Star Catalog 22 . See Table 7.AcknowledgementsThe generous assistance of Russell Genet was instrumentalin the execution of this work. Gratefulthanks to John Baxter for his review of this paper.1. Anton R., “Double and Multiple Star Measurements”,The Journal of Double Star Observations,vol 6 no 3, July 20102. Anton R., “Double and Multiple Star Measurements”,Journal of Double Star Observations, vol7 no 2, 20113. Arnold D. “Divinus Lux report #16”, Journal ofDouble Star Observations, vol. 5 no. 1 Winter20094. Arnold D., “Divinus Lux Observatory: Report #3”,Journal of Double Star Observations, vol 2 no 2,2006

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 46Astrometric Measurements of Seven Double Stars, September 2011 Report5. Arnold D., “Divinus Lux Observatory: Report #6”,Journal of Double Star Observations, vol 2 no 3,20066. Arnold D., “Divinus Lux Observatory: Report #15”,Journal of Double Star Observations, vol 4 no 4,20087. Arnold D., “Divinus Lux Observatory: Report #20”,Journal of Double Star Observations, vol 6 no 1,20108. Arnold D., “Divinus Lux Observatory: Report #23”,Journal of Double Star Observations, vol 6 no 4,20109. Bell, R., 2011, Stargazer Online,www.richardbell.net10. Burton J., 2011, Astrogeek Observatory(www.astrogeek.org)11. Daley J., “Double Star Measures for the year2005”, The Journal of Double Star Observations,vol 2 no 2, 200612. Daley J., “Double Star Measures for the year2006”, The Journal of Double Star Observationsvol 3 no 2, 200713. Dommanget J., Nys O., Catalogue des composantesd’étoiles doubles et multiples 200214. Frey T., “Visual Double Star Measurement withan Alt-azimuth Telescope”, Journal of DoubleStar Observations, vol 4 no 2 Spring 200815. Hog E., Baessgen G., Bastian U., Egret D., FabriciusC., Grossmann V., Halbwachs J., Makarov V.,Perryman M., Schwekendiek P., Wagner K.,Wicenec A., 1997, The Tycho Catalogue, 2011from its website www.rssd.esa.int16. Heijen M., Star Observer website(www.starobserver.eu) 200817. Hoffleit D., Warren W., 1991, The Bright StarCatalogue, 5th Revised Edition, Yale University18. Johnson J., Genet R., “Measurements of the DoubleStar STF 2079”, Journal of Double Star Observations,vol 3 no 4 Fall 200719. MacEvoy B., William Herschel’s Double StarCatalogs Restored, 201120. Mamajek E., Kenworthy M., Hinz P., MeyerM., “Discovery of a Faint Companion to Alcor UsingMMT Imaging”, Science Daily, 200921. Martín E, “CCD Double Star Measurements”,Journal of Double Star Observations, vol. 5 no. 1Winter 200922. Mason B., Wycoff G., Hartkopf W., Douglass G.,Worley C., 2011, Washington Double Star Catalog23. Muller R., Cerosimo J., Miranda V., Martinez C.,Cotto D., Rosado-de Jesus I., Centeno D., RiveraL., “Observation Report 2005”, Journal of DoubleStar Observations, vol. 3 no. 2 Spring 200724. Muenzler K., 2003, Eagle Creek Observatory(www.eaglecreekobservatory.org)25. Myers J., Sande C., Miller A., Warren W., TracewellD., 2002, Sky 2000 Master Star Catalog, GoddardSpace Flight Center, Flight Dynamics Division.26. Olcott W., “In Star Land with a 3 inch Telescope”,G. P, Putnam and Sons Publisher,190927. Perez J., Belt of Venus website(www.perezmedia.net) 200528. Perryman M., Lindegren L., Kovalevsky J., HogE., Bastian U., Bernacca P.L., Creze M., DonatiF., Grenon M., Grewing M., van Leeuwen F., vander Marel H., Mignard F., Murray C., Le Poole R.,Schrijver H., Turon C., Arenou F., Froeschle M.,Petersen C., 1997, The Hipparcos Catalogue ,2011 from its website www.rssd.esa.int29. SAO Staff, (1996) Smithsonian Astrophysical ObservatoryStar Catalog.30. Schlimmer J., “Double Star MeasurementsUsing a Webcam”, Journal of Double StarObservations, vol 3 no 3, 200731. Schlimmer J., “About Relative Proper Motionof 61 Cygni”, Journal of Double Star Observations,vol 5 no 2, 200932. Schlimmer J., “Double Star MeasurementsUsing a Webcam: Annual Report of 2008”,Journal of Double Star Observations, vol 5 no2, Spring 200933. Schlimmer J., “Double Star MeasurementsUsing a Webcam: Annual Report of 2009”,Journal of Double Star Observations, vol 6 no3, July 2010

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 47Astrometric Measurements of Seven Double Stars, September 2011 Report34. Schupmann L., “Ludwig Schupmann ObservatoryMeasures of Large Δm Pairs – Part Three”, TheJournal of Double Star Observations, vol 5 no 3Summer 200935. Worley C.E., Douglass G.G 1996, The WashingtonVisual Double Star Catalog36. Worley C., Douglass G., 2006 The WashingtonDouble Star Catalog37. Daley J., Schupmann L., “Double Star Measuresfor the Year 2006”, Journal of Double Star Observations,vol 3 no 2, 200938. Hirschfield A., “Parallax: the Race to Measure theCosmos”, MacMillan Press 200139. Pannekoek A., “A History of Astronomy”, CourierDover Publications, 1989

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 48Separation and Position Angle Measurements ofDouble Star STFA 46 and Triple StarSTF 1843Chandra Alduenda 1 , Alex Hendrix 1 , Navarre Hernandez-Frey 2 , GabrielaKey 3 , Patrick King 4 , Rebecca Chamberlain 1 , Thomas Frey 51. The Evergreen State College, Olympia, Washington 2. Kentridge High School, Kent, Washington3. St. Mary’s Academy, Portland, Oregon 4. Oregon Episcopal School, Portland, Oregon5. California Polytechnic State University, San Luis Obispo, CaliforniaAbstract: Various students and faculty all participated in the 2011 4th annual summerastronomy workshop at Pine Mountain Observatory. Our group was trained in the propertechniques and skills required for measuring the separation and position angle of the binarystar STFA 46 and trinary star STF 1843. We learned how to calibrate an astrometriceyepiece, make appropriate measurements, do a statistical analysis, and analyze data. Theseparation measurements our group made were comparable to current literature values.However, the observed position angles differed significantly from the literature. This discrepancyfrom literature values could be due to weather conditions or equipment limitations.IntroductionA group of students, three new and two experiencedobservers, and an instructor from The EvergreenState College (TESC) participated in thefourth annual astronomy research workshop at thePine Mountain Observatory (PMO) near Bend, Oregon.This year’s topics were visual double star measurementsand photometry. The workshop ran fromJuly 24-28, 2011.All visual double star teams adopted teamnames; ours was “Dubhe or Not Dubhe”. The alt-aztelescope used was an 18” Newtonian made by Obsession.The Celestron Micro Guide 12.5 mm illuminatedastrometric eyepiece was calibrated and thenseparation and position angle measurements weretaken. On night two, group members Hernandez-Frey, Key, and King, along with experienced observersHendrix and Alduenda, joined their instructorChamberlain and team leader Frey in observing doublestars (DS). Since there were three members withoutDS observation experience, we decided to firstFigure 1: Members of “Dubhe or Not Dubhe”. From left to right:Chandra Alduenda, Navarre Hernandez-Frey, Thomas Frey,Patrick King, Gabriela Key, Alex Hendrix, Rebecca Chamberlain

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 49Separation and Position Angle Measurements of Double Star STFA 46 AB and Triple Star ...StarSystemTable 1: Data for STFA 46 ABParallax(mas)Proper Motion(mas/year)RightAscensionDeclinationSpectralTypeSTFA 46A 47.44 -147.82 -159.01 G1.5VbSTFA 46B 47.14 -135.11 -163.78 G3VStarSystemTable 2: Data for STF 1843 ABParallax(mas)Proper Motion (mas/year)RightSpectralDeclinationAscension TypeSTF1843A 9.03 -46.84 -32.58 F5STF1843B 13.87 -50.39 -35.71 F5study the bright DS STFA 46 that had good separationso they could understand the technique. Directlyafter this, we observed the triple or trinary star (TS)STF 1843 in the constellation Bootes. The data wasanalyzed and each student was assigned a topic towrite up for the published paper. Alduenda andHendrix were assigned to write a more extensive partof the paper.BackgroundThe double star STFA 46 (also known as 16Cygni) is actually a triple star system composed of anAC-B combination. STFA 46 A (HD186408) has aclose binary (16 Cygni C) first resolved by Turner(2001). The AC binary has a separation and positionangle of 3.4 arc seconds and 209 degrees, respectively,with a projected separation of 73 AU. The C componentmay be a red dwarf (Raghavan, 2006). STFA 46B has a Jupiter-mass planet orbiting the star with aperiod of 2.2 years and an eccentricity of 0.69 (Mazeh,1996). Due to the close agreement of parallax, propermotion, and spectral types shown in Table 1, STFA 46AB is considered to be a binary pair (Hipparcos andTycho, 1997), (Simbad database).The triple star STF 1843 is in the constellationBootes. The parallax, proper motion and spectral typefor the A and B components are given in Table 2(Hipparcos Catalog, The SkyX).The values for proper motion and spectral typeindicate a very close association for both A and B sothey likely both originated in the same collapsing gascloud, indicating a possible binary relationship. Theparallax difference between A and B is converted to adistance of 38.2 parsecs (124.3 light years). The Ccomponent is a G5 star with a right ascension anddeclination proper motion of -43. 20 and +37.20, respectively(The SkyX). This indicates the star is anoptical component of the AB system.Locale and Observing ConditionsThe study was carried out at Pine Mountain Observatorynear Bend, Oregon. The Observatory is locatedat 43.79 degrees north latitude and 120.94 degreeswest longitude. Due to high winds, humidity,and dew, the first night of observation was cancelled.The second night was more favorable with somebreeziness at times that could have affected somemeasurements. The seeing was good with only moderatescintillation. At times, the transparency was notfavorable.Calibration of the Celestron AstrometricEyepieceThe linear scale on the Celestron 12.5 mm astrometriceyepiece, divided into 60 equal divisions, mustbe calibrated for each telescope-eyepiece assembly todetermine the scale constant in arc seconds per division.This has been described at length previously(Frey, 2008). The reference star Navi (Gamma Cassiopeia)was used for this calibration because its declinationlies within the recommended 60-75 degree rangefor calibration (Argyle, 2004). The results are given inTable 3. SD and ME are the standard deviation andthe standard error of the mean.Double Star STFA 46 Literature ValuesOnce the scale constant had been determined,the 18-inch Obsession was two-star aligned and thetracking motors engaged. Because several of the observerson the team were inexperienced in using analt-az telescope, a well-studied double star was chosenfor initial study; STFA 46 in the constellationReferenceStarBesselianEpochTable 3: Scale Constant DeterminationDeclination(degs)# Observ. Ave.DriftTime(secs)SD/ME(secs)ScaleConstant(asec/div)Navi 2011.561 60.717 10 83.28 0.22/0.07 10.21

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 50Separation and Position Angle Measurements of Double Star STFA 46 AB and Triple Star ...Star SystemIdentifierTable 4: Separation Measurements of STFA 46 and STF 1843.Bessel.EpochLiteratureEpoch# Observ.SD/ME(as)ObvSep(as)LitSep(as)STFA 46AB 19418+5032 2011.56 2010 15 0.51/0.13 42.9 39.7STF1843AB 14246+4750 2011.56 2007 10 0.54/0.17 20.9 19.8STF1843AC 14246+4750 2011.56 2007 10 0.30/0.10 98.9 98.8Star SystemTable 5: Position Angle Measurements for STFA 46 and STF 1843.IdentifierBessel.EpochLiteratureEpochCygnus, first studied in 1800 and most recently in2010 (Mason, 2009). The most recent WashingtonDouble Star (WDS) Catalog 2010 position angle andseparation values were 133 degrees and 39.7 arc seconds,respectively. The primary and secondary magnitudeswere 6.0 and 6.2. The right ascension and declinationof the primary star are 19h 41m 49.1s and+50° 31m 31.6s. Table 1 gives additional data forSTFA 46 AB.Triple Star STF 1843The most recent study published in the WDSCatalog of the triple star STF 1843 ABC in the constellationBootes was done in 2007, where the positionangle for the AB component was 187° and a separationof 19.8 arc seconds. The primary and secondarystars had magnitudes of 7.68 and 9.23, respectively.The STF 1843 AC position angle was 64° with a separationof 98.8 arc seconds. The C component had amagnitude of 9.72. Table 2 gives additional data forSTF 1834 ABC.Separation Measurements of STFA 46and STF 1843The telescope was two-star aligned and the servomotorsengaged. The Celestron Micro Guide eyepiecewas rotated until the central linear scale was parallelwith the axis joining the two stars. The distances betweenthe centers of the two stars was estimated tothe nearest 0.1 divisions and recorded. Then, usingthe slow motion controls, the stars were shifted to anew location along the linear scale, and a new measurementwas made. We repeated this process 10-15times, taking turns among all members of the group.# Observ.SD/ME(degs)ObvPA(degs)LitPA(degs)STFA 46AB 19418+5032 2011.56 2010 15 3.35/0.87 130 133STF 1843AB 14246+4750 2011.56 2007 10 4.64/1.47 180 187STF 1843AC 14246+4750 2011.56 2007 10 3.36/1.01 59 64This method of moving stars to new locations alongthe linear scale for each measurement was made tonegate bias errors that might exist if the stars werecontinually kept and measured at the same divisionmarks.Due to possible field rotation, the eyepiece wascontinually adjusted so that the two stars remainedaligned with the linear scale. The SD/ME are standarddeviation and standard error of the mean. Theobserved and literature separations are given in arcseconds. The separation measurements for STFA 46and STF 1843 are shown in Table 4.Position Angle Measurements of STFA46 and STF 1843The determination of the position angle using thedrift method with the alt-az telescope has been describedat length in a previous paper (Frey, 2008).Briefly, it involves disengaging the servo-motors sothat the telescope becomes a “push Dob”. The doublestar is aligned with the linear scale and adjustedmanually so, when the telescope is released, the primarystar drifts through the 30 th division mark on thelinear scale. This proper drift is difficult to do andusually takes several attempts to accomplish. Second,a parallax error can occur as the primary star crossesthe outer protractor scale that can lead to an erroneousposition angle. Third, aligning the two stars onthe linear scale becomes more challenging as theseparation becomes smaller. If not properly aligned,the position angle will be radically altered. To circumventthese potential problems, 10-15 drift cycles werecarried out, and the cycles averaged to obtain the best

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 51Separation and Position Angle Measurements of Double Star STFA 46 AB and Triple Star ...mean value.Due to possible field rotation, the eyepiece wascontinually adjusted so that the two stars remainedaligned as much as possible with the linear scale.Special effort was made to realign the stars parallelto the scale and the eyepiece tightened in the drawtube. Position angles (PA) are given in degrees. TheSD/ME are standard deviation and standard error ofthe mean. The position angle measurements for STFA46 and STF 1843 are shown in Table 5.DiscussionSeparation measurements on the two multi-starsystems were carried out using only the CelestronMicro Guide eyepiece. Table 4 shows the observed andmost recent WDS literature separation values. If theobserved separation values are compared in the orderconducted, we see for STFA 46 AB, STF 1843 AB, andSTF 1843 AC that the percent differences based onthe literature values were 8.1%, 5.5%, and 0.1%, respectively.Because three of the five students takingmeasurements had never done this before, this decreasingtrend in percent error shows that the observerswere learning observation techniques very rapidly.This is why it is wise to initiate beginning observerswith very bright and well-separated doublestars.The observed position angle measurements didnot correlate well with the literature values. Thereare many possible reasons for these errors. The observedand literature values for the position anglesare shown in Table 5. The observed position anglesfor STFA 46 AB, STF 1843 AB, and STF 1843 AC differedfrom literature values by 4, 7, and 5 degrees,respectively. Let’s account for some of these discrepancies.First, weather may have contributed to these errors.Occasional breezes would occur during a PAdrift cycle enough to nudge the “push Dob” away froma proper drift. Yet, Grubbs Critical Value outlier formula(Burke, 1998) for a 99% confidence level determinedthat none of the collected data qualified as outliersbut errant breezes could have moved the telescopeenough to alter the observed position angle.Second, to cancel out possible field rotation andbias readings, the eyepiece was rotated and realignedafter several drift cycles. In the realignment process,the eyepiece was rotated so the linear scale was coalignedwith the axis passing through the two starsand the eyepiece was tightened with a set-screw onthe draw tube. During the securing of the set-screw,the eyepiece had a tendency to rotate. So unless theeyepiece was tightly held in place while being secured,it could have rotated and thus be misalignedwith the axis of the two stars.The third and most likely explanation deals withthe separation between the two stars. This is especiallytrue of STF 1843 AB with a literature separationof 19.8 arc seconds. Because only the CelestronMicro Guide eyepiece was used to make the measurements,the scale constant was 10.2 arc seconds perdivision. So a 19.8 arc second separation spans lessthan 2 divisions on the linear scale. This is a verysmall distance to accurately align for the PA drift.Whereas a slight misalignment of this span in measuringseparations would not affect the results significantly,a small tilt in the alignment would make asignificant error in the position angle value. See Figure2.There are other possible reasons for position angleerrors observed for STFA 46 AB, some of whichcan be traced to the recorded values themselves.Eight of the fifteen values ranged between 130-133°and seven ranged from 122-129°. Seven different observersrecorded the 15 position angles in the courseof the study. In some instances, one observer wouldbegin the drift cycle (because adjusting the telescopeto the proper drift position is very difficult for some)and then switch off in mid-drift to another observer,who would watch the pair cross the protractor scaleand announce the value. We now know this is an ineffectiveprocedure. There is the possibility that theobserver could be watching the wrong star, that is,the secondary instead of the primary. This is complicatedby the fact that the two stars have almost identicalmagnitudes; 6.0 and 6.2. This would change theobserved position angle to a whole new data set. Ifonly the eight observations ranging from 130-133°were considered, the mean position angle would havebeen 131° with a standard deviation and mean errorof 1.30 and 0.46, respectively.The most severe difference between observed andliterature values of position angles occurred with STF1843 AB. As indicated in Figure 2, the 19.8 arc secondseparation makes alignment for the drift procedureespecially challenging. There were ten recorded positionangles ranging from 175-186° and the literaturevalue was 187°. Because all of the observed valueswere less than the literature value, the latter was rechecked.WDS values indicated the position angle in1830 and 2007 both having 187°. TheSkyX value was186° 37 minutes, showing close agreement. The recordedposition angles were reviewed again to make

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 52Separation and Position Angle Measurements of Double Star STFA 46 AB and Triple Star ...Figure 2: Possible Position Angle Errors Due to Misalignment on Linear Scalesure that the data was correct. Six of the ten valuesranged from 181-186° while the other four valuesranged from 175-176°. The range of observed valuesbetween separate observers in our group does not appearto be random. This outcome could have beencaused by ineffective tightening of the astrometriceyepiece in the draw tube. The eyepiece would havebeen skewed in the same direction each time leadingto consistently incorrect position angles. The four valuesbetween 175-176° were taken concurrently so allof the observers could have been looking at the secondarystar.A similar pattern of observed position angles withrespect to literature values is noted for STF 1843 AC.The ten recorded position angles ranged from 53-63°with a mean of 58°. The literature value was 64°. Theliterature values were again rechecked: WDS at 64°(2007) and TheSkyX at 63° 6 minutes. All but one ofthe observed values were less than the literaturevalue, indicating some source of systematic error. Themisaligned astrometric eyepiece is the most probablesource of error.In order to alleviate this problem in future studies,several operations are considered essential. First,for separation values less than 30 arc seconds, it isrecommended that a 2x-3x Barlow lens be used inconjunction with the astrometric eyepiece so the increasedmagnification will allow a more accuratealignment of the pair of stars on the linearscale. This should only be done, however,when the atmospheric conditions are conducive.In the case of this study, the breezefactor was too great to allow use of the Barlow.Also, since moderate scintillation waspresent it would make alignment and readingof both separation and position angledifficult. Second, limit the number of peopledoing a particular measurement to oneobserver. For this workshop the exercisesand measurements carried out were foreducation and training. However, allowingmore than one person to take a particularreading could have resulted in faulty results.Student ReflectionsThree of the five students making doublestar observations had never attempted thiskind of science research before. Their effortsincluded instrument setup, orientation,instruction, making observations,analysis, presentation of data to their peers, anddocumentation of their experiences. The following is aparaphrased summary of their reflections.The double star STFA 46 AB were two stars withmagnitudes of 6.0 and 6.2. This made it easy at timesto see the stars separation and drift as they wereclearly visible. Being able to work together as a group,having a positive attitude, helping explain to the nextperson where to look in the eyepiece and how to controlthe alt-az hand pad seemed to be extremely helpful.Other things that made data collection smoother werethe handouts the lead professor gave us. These werehandouts on how to calibrate the eyepiece, using databasesfor double star research, and data collection.Also, working with college professors offered a rareexperience for high school students, and having collegestudents with astronomical experience as team captainsdeepened the experience further. The two collegestudents in the group taught us how to make observationsand calmed fears of not getting the data corrector done in time. One way they did this was by drawinga diagram of the astrometric eyepiece and explaininghow to read measurements on it. This really helped usbecause we were not familiar with this equipment.We had a night of unfavorable weather which requiredus to do the double star and triple star meas-

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 53Separation and Position Angle Measurements of Double Star STFA 46 AB and Triple Star ...urements back to back the following night withoutchecking our double star data for errors. The triplestar STF 1843 ABC gave us additional challenges.Both stars were higher in magnitude making it moreof a challenge to see them. Also, Bootes was settingbehind the Observatory very quickly, it was still a bitbreezy, and the sky had moderate transparency due tohaze. The team knew they had to be attentive and alertto finish getting the data. We could have chosen anotherstar system that was higher in the sky and possiblyeasier to see given the conditions we had beenworking with, but we did choose this system to studyand came up with some interesting results under pressureby a team of novice and experienced observersthat required in depth analysis.AcknowledgementsThe team would like to express their thanks toTom Smith, and Joseph Carro for reviewing this paperand for their excellent suggestions. We would alsolike to thank Greg Bothun, director of Pine MountainObservatory, and to Mark Dunaway, Kent Fairfield,Allan Chambers, and Rick Kang for opening the facilitiesand for being on hand to answer questions andassist our needs.Thank you goes to Rick Watkins and ThomasFrey as co-directors this year, and to Russ Genet asworkshop advisor. Thanks to The Evergreen StateCollege staff: Dean Allen Olson, and to Peter Robinson(Director of Lab I, Lab II, and science technician)for all of your support and time given to answer questions.Appreciation also goes out to ShiLu Vanasupawho assisted in prescreening the target double andtriple stars for all teams at PMO prior to the workshop.ReferencesObserving and Measuring Visual Double Stars, R.Argyle, Springer, London 2004.Burke, M., 1998, Missing Values, Outliers, RobustStatistics, and Non-Parametric Methods, RHMTechnologies, Ltd., Scientific Data Management, 2(1), 19-24.Frey, Thomas, Spring 2008, Journal of Double StarObservations, 3(2), 59-65.Hipparcos and Tycho Catalogs, 1997.Mason, B., The Washington Double Star Catalog,2009, Astronomy Department, U.S. Naval Observatory.Mazeh, T., et.al., 1996, Astrophysical Journal, 477,L103.Ragahavan, D., et.al., 2006, Astrophysical Journal,646(1), 523-542.SIMBAD database: http://simbad.u-strasbg.fr/simbad/TheSkyX software: http://www.bisque.com/scTurner, N.H., et.al., 2001, Abstract @AstrophysicalData System, The Astronomical Journal, 121,3254.Chandra Alduenda and Alex Hendrix are students at The Evergreen State College andhave participated at the PMO summer workshops and the Oregon Star Party in 2010 and2011. Navarre Hernandez-Frey is a student at Kentridge High School, Kent, Washington.Gabriela Key is a student at St. Mary’s Academy, Portland, Oregon. Patrick King is a studentat Oregon Episcopal School, Portland, Oregon. Rebecca Chamberlain, Member of theFaculty, The Evergreen State College, teaches interdisciplinary programs that link sciences,humanities, and the arts. She has taught Earth and Sky Sciences for Antioch University'sTeacher Education Program, and has worked as the lead Science Interpreter inthe Starlab Planetarium at the Pacific Science Center. Thomas Frey is a Professor Emeritusof Chemistry at California Polytechnic State University. He was a Team Leader at thePMO Workshop 2009, the Principle Investigator of the double star group at the PMOWorkshop in 2010, and co-director of the PMO summer research workshop, 2011.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 54Comparison of Data on Iota Boötes UsingDifferent Telescope Mounts in 2009 and 2010 bythe St. Mary’s School Astronomy ClubHolly Bensel 1 , Ryan Gasik 1 , Fred Muller 1 , Anne Oursler 1 , Will Oursler 1 , Emii Pahl 1 , EricPahl 1 , Nolan Peard 1 , Dashton Peccia 1 , Jacob Robino 1 , Ross Robino 1 , Monika Ruppe 1 ,Peter Schwartz 1 , David Scimeca 1 , Trevor Thorndike 1St. Mary’s SchoolMedford, OregonAbstract: Teachers and students from St. Mary’s School in Medford, Oregon attended the2009 and 2010 Astronomy Research Workshop at Pine Mountain Observatory in Oregon.They compared the accuracy of their double star observations on an Alt-Az and equatorialtelescope mount using the star Iota Bootes. Our results showed no significant differencebetween the use of either mount.IntroductionA double star is defined by two different categories:binary systems, in which stars are closeenough relative to each other in space to have significantgravitational interactions; and optical doublestars, which are gravitationally unrelated stars thatonly appear to be near each other when viewed fromEarth. Data collection over several centuries is necessaryto determine in which category a double starbelongs. This is accomplished through detailed measurementsof separation and position angles that areused to determine the status of the system. We presentour visual measurements of the double star IotaBootes as part of our process toward becoming accurateand efficient double star observers.This project is a continuation of initial studiescarried out at the Pine Mountain ObservatorySummer Science Research Workshop in 2009. Atthat time a small group from the St. Mary’s AstronomyClub (Figure 1) worked towards and accomplishedthe composition of a paper on the neglecteddouble star ARY 52 (Frey, et. al., 2009). It was theFigure 1: St. Mary’s Astronomy Club 2010: Back Row left toright: Emma Dauterman, Corey Cattanach, Chris Ladue, CodyHolliday, Trenton Hoyle, Will Oursler, Conor Keating, NolanPeard, Ryan Gasik, Guo Zihan, Qiu Hongxiang, Jacob Robino,Conrad Stout, Peter Schwartz, Ross Robino, Tom Hilton. FrontRow left to right: Holly Bensel, Monika Ruppe, Dashton Peccia,Emii Pahl. Not Pictured: Fred Muller, Anne Oursler, Dave Scimeca,Trevor Thorndike

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 55Comparison of Data on Iota Boötes Using Different Telescope Mounts in 2009 and 2010 ...goal of this group to master techniques in the observationof double stars and to use this information intheir further research with their astronomy clubwhich is based on the campus of St. Mary’s School inMedford, Oregon. Afterwards, sixteen assorted highschool and middle school students learned how totake data on double stars and how to write a properresearch paper. Data was collected on the campustrack which is located at [42.3 o N latitude, 122.8 o Wlongitude] at an elevation of 1380 feet above sea level.Viewing conditions on the track are relatively brightbut low magnitude double stars are still clearly visiblein our telescope.After several weeks of data collection onknown double stars, and comparing our results withthose published in the Washington Double Star Catalog(Mason, 2009), the club was ready to study a“neglected” double star. A neglected double star is onethat has not been observed extensively or recently.Unfortunately, fall and winter in Southern Oregoncan be unpredictable. The fall and winter seasons ofthe 2009/2010 academic year were cloudy and rainy.The club was unable to take the telescope out untilJuly and August of 2010. In July the telescope mountwas converted from Alt-Az to equatorial using awedge. It was discovered that with the new mountcame new challenges. These challenges included unfamiliaritywith the new mount and hence difficulty inaligning the telescope.Before measurements could be obtained on theneglected stars, the group needed to be certain theycould obtain results of an equal or better quality tothose achieved when the mount was in Alt-Az configuration.Therefore, data was collected on IotaBootes, one of the double stars which the club hadgathered data on in the fall of 2009 at St. Mary’sSchool. This new data was taken during the 2010Pine Mountain Observatory Summer Science ResearchWorkshop. Pine Mountain Observatory is locatedat [43.8 o N latitude, 120.9 o W longitude] at anelevation of 6500 feet above sea level near Bend, Oregon.The dry, desert-like climate and dark skies makefor excellent viewing.HypothesisIt was hypothesized that the switch from the Alt-Az telescope mount to the equatorial mount would notresult in any significant differences in the data aslong as the telescope operators were experienced withthe new setup. However, the researchers were notexperienced with the setup, consequently it wasspeculated that the measurements might not be asFigure 2: Setting up the telescope at St. Mary’s School, 2009.Left to right: Monika Ruppe, Fred Muller, Will Oursler, MishaZavalzowski, Ryan Randall, Ryan Gasik.accurate as those made while the telescope was in themore familiar Alt-Az configuration.EquipmentThe St. Mary’s Astronomy Club uses a Meade 10”LX200 Schmidt-Cassegrain telescope which was generouslydonated by Fred Muller in 2007 (Figure 2). Inboth the 2009 and 2010 observing seasons a 12.5mmCelestron Micro Guide astrometric eyepiece was used.The telescope mount was converted from an Alt-Azconfiguration to an equatorial configuration in theJuly of 2010, leading to a few changes in the methodof operation. These changes in operation are specificto the position angle and will be described in detaillater in the paper.CalibrationThe first step in observing double stars is tocalibrate the linear scale on the astrometriceyepiece in units of arc seconds per division. Argyle(p. 152) suggests using a reference star of mediumbrightness at a declination between 60o and 75o toavoid timing errors. If the star is below 60o then thefield drift is too slow, and above 75o is too fast to allowaccurate timing. Therefore, the club used Mizar,at 59o 52.379’ declination, because it was easily visibleand close to the recommended range. The timecomponent is measured by placing the calibration staron the eastern edge of the linear scale and allowing itto drift in right ascension to the other side of thescale. This drift is timed using a stopwatch to thenearest .01 seconds. To reduce random errors, many

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 56Comparison of Data on Iota Boötes Using Different Telescope Mounts in 2009 and 2010 ...trials were made by different individuals from theclub. The average of all these trials was used to determinethe scale constant (Z) for the telescope eyepiecesystem.Z =Tave15.0411 cos( RS)Dwhere Z is the scale constant (in arc seconds per division),Tave is the average drift time, 15.0411 is thearc seconds per second of the Earth’s rotation at thecelestial equator, cos(RS) is the cosine of the referencestar’s declination, and D is the number of division onthe linear scale. This is 60 divisions for our Celestroneyepiece.The reference star used in the calculation, Mizar,had an average drift time of 47.64 s (standard deviationof 0.31s. and mean error of 0.10 s). This resultedin a scale constant of 6.85 arc seconds per division.We used this value during the 2010 Pine MountainWorkshop. We were confident of this value since werepeatedly obtained similar results on multiple nightsat St. Mary’s School during the fall of 2009. The scaleconstant data are summarized in Table 1.Separation and Position Angle Measurementof Iota BootesIota Bootes was chosen for this project because itis an extensively studied double star with knownseparation and position angle measurements. Hazysky conditions in Medford, OR made this star systemideal because the magnitudes of the two stars (4.9,7.5) were bright enough to allow effective observations.It is located at a right ascension of 14h 16.5’,and a declination of 51 o 19.25’. The Washington DoubleStar Catalog cited the separation and position angleas 38.7 arc seconds and 34 o respectively (WDS,2009). Our results are for measurements of IotaBootes are shown in Table 2.The separation between the primary and secondarystar is found by aligning the two with the linearscale and estimating the distance between them tothe nearest 0.1 division. The pair of stars are movedacross the scale periodically to reduce bias betweenmeasurements. The average of these measurements ismultiplied by the scale constant to obtain the separationin arc seconds (Argyle, p. 152).The students took twelve separation measurementsin 2009 at St. Mary’s School and made nineseparation measurements during the Pine MountainWorkshop in 2010. As mentioned earlier, the differencein operation between 2009 and 2010 was in theacquisition of the position angle. In the Alt-Az arrangementthe students used a method described byFrey (2008) and taught to St. Mary’s participants atthe 2009 Pine Mountain Workshop (Frey, et al.,2009). The astrometric eyepiece is rotated until thestars are aligned with the linear scale. The scope ismanually moved using the right ascension and thedeclination control knobs to allow the primary star todrift through the mid mark on the linear scale andmove outward to a circular protractor scale, wherethe position angle is observed and recorded to thenearest 0.5 o (Argyle, p. 153). In the equatorial configurationthe primary star was placed at the centerTable 1: Data used in the Excel spreadsheet calculation of the scale constant for a 10” LX200 Schmidt-Cassegrain telescope.EyepieceCelestron AstroReticuleStarBesselianEpochDeclination #Obs AveDriftTime(Sec)StdDevMeanErrorMizar 2011.57 54 55’ 51” 10 47.64 0.31 0.1 6.85ScaleConstantTable 2: Comparison of Separation and Position Angles of Iota Bootes in 2009 and 2010.Double Star Identifier Besselian Lit.Epoch Epoch #Obs. SD/ME Obs. Lit. %Type ofSep. Sep. Difference MountIota Bootes(2009)14162+5122 2004.09 2009 11 0.304/0.092 35.6 34 6.32 Alt-AzIota Bootes(2010)14162+5122 2010.06 2009 9 0.870/0.290 37.1 34 2.37 EquatorialDouble Star Identifier Besselian Lit.Epoch Epoch #Obs SD/ME Obs. Lit. %Type ofPA PA Difference MountIota Bootes(2009)14162+5122 2004.09 2009 15 1.24/0.32 32 38.7 3.63 Alt-AzIota Bootes(2010)14162+5122 2010.06 2009 8 2.44/0.70 32 38.7 3.93 Equatorial

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 57Comparison of Data on Iota Boötes Using Different Telescope Mounts in 2009 and 2010 ...of the linear scale using the telescope hand controllerkeypad and the eyepiece rotated so that the doublestar aligned with the linear scale. The Right Ascensionmotor was then deactivated. The position anglewas determined by observing which degree markingthe primary star crossed on the outer protractor scaleand rounding to the nearest 0.5 o . Once the starcrossed the protractor scale the motor was turned onand the procedure was repeated with the reticule rotated180 o approximately every five trials to reducebias.Conclusions and New DirectionsThe students’ separation and position angle measurementswhen using the Alt-Az telescope mountwere similar to their measurements using the equatorialmount. The percent error of the position anglewas 3.63% in 2009 and 3.93% in 2010. In 2010 therewere four outliers due to inexperienced operators.The percent error of the separation distance was6.32% in 2009 and 2.37% in 2010. The error was lessthe result of the mount and more the result of operatorerror and lack of familiarity with the telescopeconfiguration. The club will need to practice with theequatorial mount so that the alignment and otherprocedures yield more precision and accuracy.In addition to improving our operational skillsover the summer of 2011, the club plans to add photometryof double and triple star systems to our skillset.AcknowledgementsThe St. Mary’s Astronomy Club would like tothank Russell Genet, Research Scholar in Residenceat California Polytechnic State University, for providingthe workshop that gave us the experience to learnabout double stars. We would also like to thank ThomasFrey for his guidance and support. We want tothank the Pine Mountain Observatory for making theobservatory available for workshops. We thank FredMuller for donating the telescope and Dave Scimecafor donating technical expertise his time. Acknowledgementis also directed to the faculty and staff atSt. Mary’s School for providing facilities and financialsupport to the astronomy club.ReferencesObserving and Measuring Visual Double Stars, Argyle,Robert., Springer, London, 2004.Frey, Thomas G., October 2008, Journal of DoubleStar Observations, 3(2), p. 59-65.Frey, Thomas G., October 2009, Journal of DoubleStar Observations, 5(4), p. 212-216.Mason, Brian. The Washington Double Star Catalog.July 2009. Astronomy Department, U.S. NavalObservatory. http://ad.usno.navy.mil/wds/wds.html.Holly Bensel is a science teacher at St. Mary’s School in Medford, Oregon. FredMuller is a retired science teacher and a substitute teacher at St. Mary’s School. DaveScimeca is a retired technician from Ames Research Center. Ryan Gasik, AnneOursler, Will Oursler, Emii Pahl, Eric Pahl, Nolan Peard, Dashton Peccia, JacobRobino, Ross Robino, Monika Ruppe, Peter Schwartz, and Trevor Thorndike are currentand former high school students at St. Mary’s School in Medford, Oregon.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 58351 New Common Proper-Motion Pairs from theSloan Digital Sky SurveyRafael CaballeroAgrupación Astronómica HubbleMartos, Jaén, SpainEmail: rafa@sip.ucm.esAbstract: This paper presents 351 previously uncataloged pairs with separation under 100 arcsecondsand proper motion over 70 milliseconds of arc/year. These pairs are the result of an extensive study thatstarted with 96,205 candidate pairs from the Sloan Digital Survey (SDSS). Different criteria explained inthe paper are applied to increase the probability of a physical bound between the components.IntroductionThis paper presents 351 new common proper motionpairs (CPMP’s) obtained from the seventh datarelease of the Sloan Digital Sky Survey (SDSS-DR7,Abazajian et al. 2009). The characteristics of thepairs are:• Separation between 6 and 100 arcseconds• Proper motion over 70 milliseconds of arc/yearThe idea of using the SDSS for obtaining newpairs is not new. A first list of wide double stars inthis catalog was proposed by Sesar, Ivezić, andJurić (2008). By using the DR6 version of the catalogthe authors considered stars with proper motion over15 milliseconds of arc/year, matched components towithin 5 milliseconds of arc/year, and identified22,000 total candidates with excellent completeness,but with a one third of them expected to be falsepositives. Also, Longhitano and Binggeli (2010), presenteda statistical research based on this catalog.However, due to the large number of false positives,the results of these papers could not be included inthe the WDS (Washington Double Star Catalog, Masonet al., 2003). Dhital et al. (2010) takes a differentapproach, trying to minimize the number of falsepositives. The more than 1000 pairs obtained havebeen included in the WDS.The purpose of this paper is similar: startingwith a set of candidates from the SDSS, we use severalfilters, either based on statistical or on physicalproperties, with the goal of eliminating chance alignmentsof stars. We also have checked the results,verifying that all the pairs presented appear withnoticeable movement in the Aladin plates (Bonnarelet al., 2000). The CPMP’s data and images obtainedcan be downloaded from http://gpd.sip.ucm.es/rafa/astro/sdssInitial set of candidate pairsIn previous projects we had obtained the initialset of stars using VizieR (available from http://vizier.u-strasbg.fr/viz-bin/VizieR). However, this projectinvolves a much larger number of stars, and atimeout error was obtained in VizieR when trying toobtain the initial set of stars. Fortunately, the SDSSproject includes a Catalog Archive Server query tool(available from http://casjobs.sdss.org/CasJobs/ ). Inparticular this tool allows the user to define directly

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 59351 New Common Proper-Motion Pairs from the Sloan Digital Sky Surveytheir SQL queries and save the result in the server.We started downloading those stars with r magnitude 0;where the subscript 1 is assigned to the brighter component,must be satisfied. This condition requiresthat the component with bluer g - i color be brighterin the r band. This filter reduced the number of candidatesto about 4723 pairs.4. Reduced Proper Motion criterionThe Reduced Proper Motion (RPM) discriminatorproposed by Salim & Gould (2003) requires both the Vand J magnitudes for each component. In particular,the V magnitude was difficult to obtain for the fainterstars. In the cases where it was possible (about 60%of the sample), the criterion was applied. This eliminatedabout 20 pairs of the candidate set.5. Checking the photographic platesThis step is necessary because all the catalogsinclude many errors, usually introduced during thecatalog generation. Therefore, every pair was checkedfor two stars with noticeable motion and roughly thesame astrometry data in the expected position. Thiswas done applying the assoc and the RGB utilitiesincluded in Aladin. The surveys employed were thePOSS I and POSS II plates corresponding to the PalomarObservatory Sky Surveys (Reid et al., 1991), andthe SERC for the parts of the sky not covered byPOSS II. The result of this last step was that only 351of the 4700 candidates can be seen in the plates asCPMPs. Table 1 includes the data of the new pairs.The complete set of RGB compositions can be seen at:http://gpd.sip.ucm.es/rafa/astro/sdss/images/photo.htmlConclusionsThe great numbers of surveys that can be accessedonline provide an important resource for amateurs.In particular, they allow us to find new possiblebinaries. However, in order to increase the quality ofthe results, different criteria must be employed inorder to eliminate as many line-of-sight pairs as possible.Although we cannot ensure that the 351CPMP’s proposed in this paper are true binaries, the

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 60351 New Common Proper-Motion Pairs from the Sloan Digital Sky Surveynumber of criteria applied indicate that they are atleast good candidates that deserve a deeper study.AcknowledgementsThe author thanks John Greaves for suggestionsand helpful comments. This research makes use ofthe ALADIN Interactive Sky Atlas and of the VizieRdatabase of astronomical catalogs, all maintained atthe Centre de Données Astronomiques, Strasbourg,France, and of the data products from the Two MicronAll Sky Survey, which is a joint project of the Universityof Massachusetts and the Infrared Processingand Analysis Center / California Institute of Technology,funded by the National Aeronautics and SpaceAdministration and the National Science Foundation.This work partially supported by the Spanish projectsTIN2008-06622-C03-01, S2009TIC-1465, and UCM-BSCH-GR58/08-910502.ReferencesAbazajian, K. N.; Adelman-McCarthy, J, K.; Agüeros,M, A.; Allam, S. S.; Allende Prieto, C.; An, D.;Anderson, K. S. J.; Anderson, S. F.; Annis, J.;Bahcall, Neta A.; and 194 coauthors, 2009, “TheSeventh Data Release of the Sloan Digital SkySurvey”, The Astrophysical Journal Supplement,182- 2, id. 543-558.Bonnarel, F.; Fernique, P.; Bienaymé, O.; Egret, D.;Genova, F.; Louys, M.; Ochsenbein, F.;Wenger, M.; Bartlett, J. G.; 2000, “The ALADINinteractive sky atlas. A reference tool for identificationof astronomical sources”, Astronomy andAstrophysics Supplement, 143, p.33-40.Dhital, S.; West, A. A.; Stassun, K. G.; Bochanski, J.J., 2010, “Sloan Low-mass Wide Pairs of KinematicallyEquivalent Stars (SLoWPoKES): ACatalog of Very Wide, Low-mass Pairs” The AstronomicalJournal, Volume 139, Issue 6, pp. 2566-2586.Halbwachs, J.L., 1986, “Common proper motion starsin the AGK3”. Bull. Inf. Centre Donnees Stellaires,30, p.129.Longhitano, M.; and Binggeli, B.; 2010, “The WidestBinary Stars: A Statistical Approach”, AstronomicalSociety of the Pacific, 435, 67.Mason, B. D.; Wycoff, G.; Hartkopf, W. I., 2003, “TheWashington Double Star Catalog”, http://ad.usno.navy.mil/wds/Reid, I. N.; Brewer, C.; Brucato, R. J.;McKinley, W. R.; Maury, A.; Mendenhall, D.;Mould, J. R.; Mueller, J.; Neugebauer, G.; Phinney,J.; and 3 coauthors, 1991, “The second PalomarSky Survey”, Astronomical Society of the Pacific103, 661-674.Salim, S.; Gould, A., 2003, “Improved Astrometry andPhotometry for the Luyten Catalog. II. FaintStars and the Revised Catalog”, The AstrophysicalJournal, 582, 1011-1031.Sesar, B.; Ivezić, Ž.; Jurić, M.; 2008, “Candidate DiskWide Binaries in the Sloan Digital Sky Survey”,Astrophysical Journal, 689, 1244.Table begins on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 61351 New Common Proper-Motion Pairs from the Sloan Digital Sky SurveyRA DEC (2000) Mags Angle Separation DATE PM-A PM-B00 16 26.98 -11 55 51.2 15.21 18.96 59.89 10.80 1994.952 +102.0 +2.0 +107.0 +5.000 17 05.88 -12 04 44.6 16.58 17.01 117.47 80.26 1994.952 +88.0 -14.0 +88.0 -9.000 21 16.56 -09 55 03.9 15.68 18.95 4.75 21.03 2000.737 +83.0 +3.0 +84.0 +3.000 46 36.93 -22 41 52.2 13.09 14.39 290.99 36.08 1994.985 +55.0 -56.0 +55.0 -56.001 02 18.55 +00 25 39.1 15.08 18.09 0.37 63.90 2002.679 +85.0 -28.0 +85.0 -32.001 11 50.94 +26 46 16.8 14.17 17.67 234.99 20.77 2004.653 +38.0 -68.0 +34.0 -69.001 12 50.16 +20 06 50.2 14.50 14.85 334.12 20.91 2004.707 +76.0 -45.0 +78.0 -46.001 19 29.98 -00 02 29.5 14.46 16.05 119.94 18.58 2001.890 -10.0 -149.0 -8.0 -149.001 19 33.88 +24 49 56.1 16.52 16.79 266.24 64.53 2004.707 -12.0 -72.0 -9.0 -71.002 17 23.13 +70 45 37.4 16.70 18.34 148.42 31.64 2005.841 -59.0 +73.0 -61.0 +71.002 20 13.79 +05 34 36.2 16.78 17.35 97.92 28.51 2005.781 +15.0 -71.0 +14.0 -69.002 32 43.91 +74 08 54.7 18.31 18.51 160.89 14.76 2005.841 +211.0 -57.0 +207.0 -56.002 33 01.17 +01 05 38.8 15.63 16.09 344.56 29.13 2001.890 +134.0 -47.0 +147.0 -44.002 46 54.25 -02 18 59.1 13.48 19.53 307.29 23.72 1996.242 +73.0 -11.0 +73.0 -14.003 04 29.29 +00 03 20.4 15.43 16.27 186.09 84.41 2002.679 +80.0 -28.0 +82.0 -27.003 04 50.47 +37 56 10.2 18.49 18.95 129.20 8.01 1994.172 +130.0 -60.0 +122.0 -56.003 05 46.37 +01 45 40.7 16.39 17.54 333.30 28.47 2004.954 -17.0 -131.0 -12.0 -130.003 06 35.88 +00 25 47.5 15.48 16.43 335.84 30.03 2002.679 -38.0 -69.0 -40.0 -66.003 15 26.76 +02 27 31 13.95 19.04 58.54 21.48 1995.051 +36.0 -67.0 +36.0 -68.003 17 45.82 +00 59 36.2 18.00 19.16 97.04 11.91 2002.679 -51.0 -53.0 -56.0 -55.003 26 36.25 +05 10 11.7 15.95 16.36 84.78 41.13 2004.953 +73.0 -4.0 +79.0 +1.003 48 20.76 +11 03 14.4 17.98 18.07 308.30 54.01 1995.051 -11.0 -74.0 -8.0 -71.003 52 48.82 +00 19 28.6 15.96 18.19 102.53 16.58 2001.890 -42.0 -106.0 -42.0 -100.004 23 16.87 +17 00 41.6 16.18 17.64 335.36 28.31 1995.051 +85.0 -11.0 +86.0 -6.004 30 06.37 +09 02 27.8 15.57 16.23 251.98 16.11 1995.076 -33.0 -69.0 -31.0 -71.004 48 04.93 +59 40 35.2 16.40 16.40 358.24 22.09 2004.790 +86.0 -71.0 +83.0 -69.005 06 12.74 +61 31 46 14.76 18.97 78.60 43.05 2004.951 +55.0 -59.0 +58.0 -65.005 30 46.74 -00 34 04.3 15.84 18.01 283.66 15.11 1996.124 -84.0 -128.0 -83.0 -131.005 31 09.56 +63 20 40.6 15.53 17.99 71.93 27.13 2004.951 +44.0 -112.0 +48.0 -115.005 39 45.69 +19 04 19.6 15.01 19.03 248.03 19.61 1995.076 +20.0 -72.0 +25.0 -77.006 07 52.65 +35 20 30.5 14.40 18.00 23.02 11.93 1995.065 +44.0 -80.0 +46.0 -80.006 13 55.36 +05 14 22.6 13.99 17.72 46.35 67.24 1996.125 +7.0 -78.0 +13.0 -76.006 40 27.16 +64 15 14.3 14.91 16.91 25.07 14.38 2004.951 +11.0 -140.0 +11.0 -137.007 27 50.79 +42 28 19 15.99 17.83 172.80 32.09 2003.886 +53.0 -146.0 +52.0 -145.007 28 20.78 +31 00 11.7 15.06 17.83 296.12 9.40 1995.128 +25.0 -143.0 +20.0 -141.007 35 40.38 +27 49 25.3 15.53 16.77 102.42 17.56 2001.966 -83.0 -52.0 -81.0 -52.0Table continued on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 62351 New Common Proper-Motion Pairs from the Sloan Digital Sky SurveyRA DEC (2000) Mags Angle Separation DATE PM-A PM-B07 47 23.50 +24 38 23.7 18.10 18.82 312.08 35.78 2000.740 +136.0 -68.0 +137.0 -70.007 58 50.08 +46 26 41.6 15.57 17.53 326.97 12.99 2000.315 -88.0 +7.0 -88.0 +6.008 00 30.27 +51 31 54.6 13.86 17.67 164.76 17.57 2003.886 -9.0 -75.0 -12.0 -70.008 01 29.38 +19 40 39.5 13.83 18.96 131.35 57.41 2004.129 +29.0 -81.0 +28.0 -80.008 04 49.03 +19 20 00.9 12.40 16.12 301.03 39.20 2004.209 -31.0 -72.0 -31.0 -69.008 05 19.03 +11 06 44.6 14.74 17.75 296.37 14.96 2005.830 +36.0 -83.0 +39.0 -82.008 05 32.28 +31 24 51.6 12.94 18.66 120.92 25.07 2001.890 -38.0 -98.0 -37.0 -102.008 09 32.51 +54 06 26.6 16.23 18.97 180.52 64.75 2003.913 +20.0 -69.0 +16.0 -69.008 14 12.84 +14 08 49.6 15.69 18.33 36.07 21.97 2004.970 -66.0 -69.0 -62.0 -72.008 14 43.65 +46 50 36.5 15.84 18.62 8.70 15.97 2000.740 -48.0 -73.0 -46.0 -71.008 19 47.96 +42 27 24.9 14.74 18.68 9.23 29.90 2000.979 -8.0 -94.0 -1.0 -94.008 20 02.34 +48 23 19.8 15.21 16.25 291.54 45.19 2000.258 -108.0 -78.0 -106.0 -77.008 20 59.44 +17 02 48.7 18.27 19.54 283.35 30.62 2004.946 +55.0 -76.0 +57.0 -82.008 22 00.54 +82 16 30.5 15.21 16.61 26.13 28.62 1994.235 -58.0 -47.0 -59.0 -53.008 22 31.76 +37 27 47.6 13.41 19.18 50.77 32.97 2001.967 -48.0 -130.0 -41.0 -129.008 25 06.62 +12 13 47.5 17.85 18.15 124.45 51.19 2005.194 -51.0 -55.0 -54.0 -62.008 25 52.69 +29 25 16.8 18.87 19.35 288.26 16.30 2002.950 -39.0 -86.0 -31.0 -83.008 29 25.73 +30 33 45.5 13.49 16.60 312.89 16.91 2002.950 -59.0 -58.0 -54.0 -60.008 30 00.61 +28 14 21.5 15.06 18.29 307.04 37.21 2002.999 -104.0 -49.0 -110.0 -57.008 30 55.74 +32 59 21.1 17.15 18.84 157.46 65.15 2002.106 -32.0 -66.0 -41.0 -63.008 31 04.59 +15 08 59.6 15.57 17.06 284.76 47.17 2005.047 +52.0 -54.0 +53.0 -54.008 32 49.93 +11 56 13.5 14.60 19.27 250.65 18.58 2005.860 +4.0 -73.0 +11.0 -72.008 33 12.08 +26 45 51.7 14.80 18.84 207.83 43.02 2003.078 -84.0 -30.0 -90.0 -37.008 33 51.86 +24 26 12.8 17.64 19.29 69.67 42.67 2003.971 -61.0 +121.0 -63.0 +117.008 33 54.63 +12 19 48.3 13.64 14.62 295.73 38.68 2001.145 +59.0 -46.0 +58.0 -46.008 34 48.64 +22 57 52 15.32 18.31 300.68 27.69 2004.211 -54.0 -89.0 -63.0 -93.008 37 33.67 +24 41 31.6 14.51 18.36 132.78 99.64 2004.130 -158.0 -121.0 -154.0 -128.008 39 42.71 +18 01 25.4 15.31 16.30 206.05 28.22 2001.146 -86.0 +9.0 -83.0 +10.008 43 34.72 +63 08 26.8 15.03 17.78 199.41 19.56 2003.914 -46.0 -60.0 -45.0 -61.008 43 54.05 +58 28 47.1 16.08 16.96 347.24 23.29 2003.810 -26.0 -72.0 -28.0 -75.008 46 24.02 +24 02 12.4 16.80 17.32 110.30 22.20 2004.212 -79.0 -71.0 -78.0 -73.008 50 53.57 +57 57 32.2 13.95 16.29 282.79 45.72 2003.812 -57.0 -73.0 -62.0 -69.008 51 35.02 +35 31 45.7 14.62 17.81 191.08 18.74 2002.106 -42.0 -91.0 -39.0 -90.008 52 31.52 +54 44 01.9 14.11 19.14 152.45 29.75 2001.213 +6.0 -118.0 +14.0 -117.008 56 16.24 +13 32 26.7 14.03 15.39 255.86 99.30 1994.172 -35.0 +113.0 -38.0 +113.009 08 52.09 +25 28 09.1 13.06 18.40 66.65 44.39 2004.288 -58.0 -57.0 -54.0 -63.0Table continued on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 63351 New Common Proper-Motion Pairs from the Sloan Digital Sky SurveyRA DEC (2000) Mags Angle Separation DATE PM-A PM-B09 10 03.05 +21 32 59.8 15.90 17.92 189.14 24.42 2004.956 -76.0 -19.0 -76.0 -13.009 12 13.45 +28 38 06.5 18.52 19.41 295.66 36.81 2004.209 -18.0 -74.0 -18.0 -78.009 13 23.70 +47 09 08.4 12.89 19.07 138.47 14.88 2001.290 +44.0 -67.0 +50.0 -73.009 17 59.87 +51 38 16 15.18 15.45 184.76 24.41 2001.287 -83.0 -72.0 -77.0 -67.009 25 07.78 +63 58 18.1 14.27 16.07 296.17 14.20 2001.457 -61.0 -108.0 -63.0 -105.009 26 34.96 +45 47 22.9 13.90 16.99 259.14 13.37 2001.890 +6.0 -70.0 +6.0 -70.009 27 54.14 +28 38 21.7 14.66 16.82 115.43 45.78 2004.212 -102.0 -50.0 -105.0 -52.009 29 44.91 +24 32 01.8 15.16 15.92 84.89 27.31 2004.367 -26.0 -93.0 -22.0 -95.009 29 58.48 +35 51 40.5 14.53 17.91 68.23 11.45 2003.067 -52.0 -47.0 -48.0 -52.009 30 07.88 +05 43 01.4 15.35 16.70 203.78 11.13 2002.12 +83.0 -94.0 +85.0 -98.009 30 10.14 +39 19 44 14.51 15.46 289.88 15.35 2002.851 -57.0 -52.0 -59.0 -53.009 35 18.99 +52 31 37.4 14.95 15.80 194.75 14.30 2001.287 -6.0 -91.0 -9.0 -92.009 35 31.66 +15 14 10.6 17.47 17.70 85.45 15.99 2005.356 -120.0 +5.0 -122.0 +1.009 35 58.70 +52 41 36.4 12.78 16.81 253.18 16.03 2001.287 -56.0 -68.0 -57.0 -73.009 36 35.32 +60 39 24.6 14.08 15.62 173.11 65.63 2000.321 -55.0 -46.0 -55.0 -46.009 42 22.52 +64 22 23 13.05 18.39 277.53 14.80 2003.81 -174.0 -61.0 -172.0 -60.009 42 41.04 +33 33 38.9 14.75 16.39 242.62 45.59 2003.316 -75.0 -12.0 -73.0 -11.009 49 53.28 +50 17 15.2 16.35 16.39 310.57 21.22 2001.888 -86.0 -28.0 -92.0 -24.009 51 24.13 +24 55 51.5 16.87 18.57 84.16 21.48 2004.951 +51.0 -56.0 +53.0 -57.009 54 23.33 +42 19 45.4 16.27 16.56 229.54 27.21 2002.851 -71.0 +19.0 -73.0 +15.009 54 35.54 +26 58 00.1 16.84 17.43 336.50 28.97 2004.367 -26.0 -79.0 -27.0 -77.009 55 25.45 +13 42 37.5 16.13 17.68 206.93 57.95 1994.326 +51.0 -56.0 +49.0 -53.009 57 03.39 +26 39 04.2 13.69 15.98 101.29 50.57 2004.946 -71.0 -32.0 -68.0 -35.010 00 17.81 +68 29 03.4 17.79 18.70 13.34 15.51 2003.914 -47.0 -62.0 -42.0 -66.010 02 43.44 +40 09 48.2 15.68 17.57 33.03 29.96 2002.999 -127.0 -24.0 -125.0 -19.010 02 50.04 +10 05 39.4 12.46 17.33 314.47 69.96 2002.953 -47.0 -73.0 -46.0 -72.010 04 17.82 +47 31 51.7 16.23 18.28 334.91 26.42 2002.035 -79.0 +10.0 -77.0 +5.010 06 23.07 +07 12 12.6 16.03 18.91 175.40 18.46 2001.788 +35.0 -67.0 +34.0 -65.010 09 38.24 +40 41 14.3 16.76 17.02 203.84 35.29 2002.999 -60.0 -73.0 -64.0 -72.010 10 15.24 +47 25 07.6 14.16 15.19 134.42 19.58 2001.970 -19.0 -70.0 -20.0 -71.010 10 18.68 +01 07 19.8 16.88 18.21 113.92 8.64 2000.979 -106.0 +35.0 -99.0 +36.010 14 01.60 +03 05 50.3 18.26 18.32 277.62 26.50 2000.343 +106.0 -104.0 +104.0 -102.010 14 12.19 +31 18 13.3 14.41 18.22 262.37 43.05 2004.291 -81.0 -35.0 -88.0 -34.010 14 31.93 +01 53 09.7 15.48 17.21 225.95 21.24 2000.343 -131.0 -50.0 -127.0 -54.010 22 08.98 +34 27 02 17.62 17.97 70.55 28.14 2004.212 -65.0 -30.0 -63.0 -31.010 23 50.47 +31 52 45.5 15.67 15.96 38.64 39.33 2004.288 -70.0 +7.0 -72.0 +7.0Table continued on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 64351 New Common Proper-Motion Pairs from the Sloan Digital Sky SurveyRA DEC (2000) Mags Angle Separation DATE PM-A PM-B10 25 20.17 +30 57 42.1 18.23 18.91 112.64 35.09 2004.288 -78.0 -65.0 -83.0 -62.010 28 54.79 +33 48 01.7 14.41 16.93 285.76 20.29 2004.083 -42.0 -67.0 -42.0 -65.010 29 58.12 +00 43 16.8 11.69 17.81 274.82 30.44 1999.220 +29.0 -88.0 +38.0 -85.010 31 03.06 +05 59 39.5 18.74 18.80 32.11 28.27 2002.120 -39.0 -85.0 -32.0 -85.010 32 18.86 +27 59 25.9 13.22 15.98 265.67 30.38 2004.957 -71.0 +19.0 -68.0 +19.010 37 28.27 +29 31 32.8 13.02 16.45 324.77 43.96 2004.970 -80.0 -59.0 -76.0 -59.010 38 41.16 +02 06 38.4 12.80 17.98 303.01 24.75 2000.979 -89.0 +6.0 -90.0 +7.010 40 15.25 +36 05 31.6 14.01 17.04 177.18 19.96 2003.316 -24.0 -78.0 -22.0 -72.010 40 25.69 +61 53 25.8 13.3 0 17.99 127.72 40.92 2002.120 -82.0 -102.0 -81.0 -110.010 45 01.14 +25 37 15.4 15.34 18.46 298.65 9.85 2004.973 -91.0 -33.0 -96.0 -38.010 50 04.73 +59 51 50.1 14.23 16.00 113.02 13.52 2000.908 -54.0 -60.0 -51.0 -63.010 50 12.05 +32 41 10.2 16.01 18.57 287.82 8.95 2004.291 -75.0 +20.0 -67.0 +23.010 50 47.21 +62 04 48.5 18.18 18.31 48.92 19.26 2000.258 -70.0 -13.0 -78.0 -16.010 53 06.72 +03 40 17.7 13.49 18.79 129.47 24.33 2001.140 -88.0 +2.0 -85.0 +3.010 54 16.19 +00 02 58.8 15.40 16.90 117.27 42.13 1995.541 +104.0 -102.0 +109.0 -103.010 59 46.73 +22 42 46.7 18.09 18.36 352.33 25.12 2005.096 +35.0 -98.0 +36.0 -94.011 00 05.29 +42 43 18.2 16.53 18.76 322.85 12.03 2003.226 -46.0 -80.0 -47.0 -80.011 02 01.89 +23 53 07.9 15.52 16.60 118.95 97.80 2002.350 -146.0 -96.0 -146.0 -92.011 02 24.47 +24 35 44.5 14.62 18.62 226.84 63.78 2005.096 -123.0 -5.0 -120.0 -8.011 02 47.68 +30 18 45 14.37 17.75 310.00 17.47 2004.362 -95.0 -11.0 -99.0 -7.011 07 53.89 +41 54 58.1 12.30 18.60 90.21 60.26 2003.313 -97.0 +3.0 -99.0 +1.011 09 51.06 +47 37 08.6 14.12 18.35 301.79 10.49 2002.106 -112.0 -9.0 -114.0 -6.011 11 42.91 +06 32 45.8 14.25 18.80 166.13 13.20 2002.120 +34.0 -73.0 +40.0 -80.011 11 57.06 +04 58 22.4 15.18 17.77 289.02 24.58 2001.290 -87.0 -55.0 -88.0 -51.011 15 22.27 +02 51 32.3 17.04 18.33 186.90 47.77 2000.343 +75.0 -32.0 +67.0 -40.011 15 48.96 +32 02 14.4 14.02 18.88 156.89 38.88 2004.362 +5.0 -84.0 +8.0 -87.011 16 44.03 +07 14 06.5 14.41 17.64 246.97 22.98 2003.248 +44.0 -66.0 +49.0 -66.011 18 21.04 +29 13 08 17.74 18.53 237.84 16.48 2004.951 -106.0 -28.0 -100.0 -25.011 20 12.17 +25 28 21.5 15.92 16.57 116.30 21.60 2005.096 -19.0 -113.0 -19.0 -110.011 21 45.09 +02 16 58 14.41 18.88 98.67 10.60 2000.979 +9.0 -131.0 +12.0 -141.011 21 58.65 +54 44 48.7 15.68 15.95 163.5 30.97 2002.999 -77.0 -44.0 -74.0 -46.011 26 44.77 +25 03 16.3 16.32 17.68 355.39 12.35 2003.076 -80.0 -38.0 -78.0 -39.011 27 24.67 +04 35 06.4 12.67 15.84 259.48 64.66 2001.290 -74.0 +3.0 -74.0 +2.011 29 59.10 +24 47 06.6 15.67 16.89 75.64 19.82 2005.096 -76.0 -4.0 -75.0 -3.011 31 42.15 -08 44 51.5 16.51 18.55 183.90 25.57 1994.266 -90.0 +7.0 -96.0 +7.011 33 30.32 +33 08 29.5 13.62 16.79 211.24 56.84 2004.367 -110.0 -9.0 -107.0 -13.0Table continued on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 65351 New Common Proper-Motion Pairs from the Sloan Digital Sky SurveyRA DEC (2000) Mags Angle Separation DATE PM-A PM-B11 33 59.84 +16 56 46.8 17.11 17.50 328.79 64.55 2005.427 -130.0 -46.0 -124.0 -47.011 35 40.32 +04 57 29.7 15.42 19.60 30.53 10.16 2001.290 -239.0 +43.0 -230.0 +34.011 37 15.80 +31 56 52.3 15.78 17.41 261.54 26.29 2004.368 -147.0 -17.0 -146.0 -21.011 39 30.94 -02 08 16.4 15.25 17.91 128.75 13.26 2000.116 -102.0 +62.0 -99.0 +67.011 40 07.53 +37 57 43.2 12.37 16.17 196.41 18.55 2003.087 -91.0 -3.0 -93.0 -8.011 43 42.12 +54 57 44.4 15.80 17.58 175.93 29.45 2001.964 -91.0 +24.0 -91.0 +22.011 44 08.82 +19 14 20.5 14.87 16.47 212.75 15.15 2005.252 -106.0 -18.0 -105.0 -15.011 44 54.22 +14 26 20.9 14.22 18.88 203.08 31.78 2003.076 -93.0 -45.0 -93.0 -41.011 45 10.15 +31 50 01.2 14.11 17.54 138.83 29.10 2004.362 -75.0 +49.0 -77.0 +50.011 45 17.40 +03 19 25.7 13.76 16.27 316.95 87.84 2000.343 -76.0 -118.0 -75.0 -120.011 45 46.44 +17 50 40.2 14.90 16.68 351.08 87.43 2003.180 -122.0 +19.0 -123.0 +15.011 46 46.23 -03 33 54.7 13.72 17.48 175.82 61.84 2000.171 -82.0 +24.0 -82.0 +16.011 46 57.13 +20 56 18.6 15.20 15.23 261.60 25.31 2005.252 -83.0 -13.0 -80.0 -8.011 47 02.29 +35 04 32.2 14.55 17.84 303.54 12.15 2004.283 -71.0 +20.0 -73.0 +19.011 48 01.80 +23 56 56.7 14.77 16.71 172.97 52.07 2005.050 -87.0 +9.0 -85.0 +8.011 51 47.12 +27 02 36.3 12.85 15.54 212.79 20.67 2004.973 -76.0 -32.0 -82.0 -33.011 51 47.28 +17 00 11.6 14.83 17.84 157.01 12.19 2005.416 -79.0 +6.0 -72.0 +7.011 53 01.76 +45 12 51.4 15.70 16.98 94.56 30.41 2003.226 -76.0 -43.0 -74.0 -40.011 54 13.29 +20 23 20.2 14.90 16.37 74.72 14.75 2003.322 -73.0 +7.0 -70.0 +7.011 58 09.14 +05 42 54.2 12.41 15.44 81.81 69.59 2003.407 -73.0 +25.0 -70.0 +25.011 59 48.15 -03 15 16.9 14.68 17.41 353.62 24.73 2000.171 -70.0 +5.0 -72.0 +6.012 00 21.27 +09 09 32.1 14.98 18.76 157.50 9.94 2002.194 -102.0 0.0 -103.0 -6.012 00 47.62 +26 11 44 14.18 14.37 250.78 21.88 2003.472 -67.0 -22.0 -72.0 -24.012 01 27.52 +21 27 28.3 12.15 18.85 294.85 21.92 2005.189 +15.0 -131.0 +17.0 -134.012 03 01.61 +11 05 11.5 12.52 15.64 144.79 17.52 2002.944 -57.0 -90.0 -56.0 -98.012 03 10.93 +49 48 50.9 17.40 18.91 164.54 19.30 2003.809 -98.0 -39.0 -98.0 -37.012 04 21.77 +63 00 48.1 15.85 18.36 186.40 91.47 2000.908 -103.0 -43.0 -102.0 -42.012 04 41.04 +09 16 56.3 15.18 17.91 251.99 81.39 2002.194 -80.0 -35.0 -71.0 -40.012 06 02.12 +12 18 18.1 13.66 16.49 269.49 38.12 2003.245 -11.0 -184.0 -5.0 -182.012 06 41.64 +66 20 57.7 12.64 17.68 56.39 48.39 2000.264 -74.0 -14.0 -73.0 -16.012 09 21.21 +06 39 15.9 15.25 17.99 74.43 8.55 2003.248 -89.0 +23.0 -80.0 +24.012 10 32.69 +33 16 13.3 15.75 16.74 303.81 13.75 2004.316 -89.0 -12.0 -94.0 -14.012 12 36.34 +23 47 20.6 14.78 15.47 173.10 27.82 2005.252 -83.0 -68.0 -83.0 -67.012 17 58.15 +27 51 27.8 12.73 17.61 330.59 37.02 2005.050 -82.0 +20.0 -82.0 +17.012 21 48.21 +04 32 26.8 15.99 17.46 243.50 74.40 2005.435 +39.0 -85.0 +36.0 -80.012 22 44.44 +03 24 40.1 14.44 17.96 338.86 39.74 2000.343 -125.0 +62.0 -120.0 +54.0Table continued on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 66351 New Common Proper-Motion Pairs from the Sloan Digital Sky SurveyRA DEC (2000) Mags Angle Separation DATE PM-A PM-B12 23 16.53 +66 45 38.8 15.61 17.99 313.05 33.43 2000.264 -83.0 -51.0 -83.0 -49.012 26 33.24 -02 10 05.8 13.92 14.18 336.25 12.74 2000.116 +53.0 -114.0 +49.0 -105.012 30 50.45 +54 08 00.4 16.69 17.73 139.74 8.83 2002.248 -85.0 +1.0 -89.0 -6.012 31 43.49 +63 54 30.9 12.75 16.77 122.94 17.86 2001.072 -110.0 -6.0 -108.0 -7.012 34 59.74 +20 26 26.5 16.53 18.85 191.54 32.19 2005.356 -75.0 +26.0 -77.0 +28.012 35 14.00 +53 36 03.5 14.07 16.98 76.15 79.90 2002.036 -77.0 -65.0 -83.0 -57.012 35 32.66 +17 52 16.6 16.13 18.12 325.87 22.91 2005.430 +77.0 -57.0 +75.0 -59.012 36 13.33 +14 57 16.5 15.80 17.74 14.23 80.54 2003.076 -158.0 -107.0 -157.0 -107.012 39 34.60 +18 17 17.4 16.57 18.39 282.08 44.59 2005.416 -56.0 -75.0 -58.0 -81.012 40 08.25 +37 21 46.1 14.33 17.19 76.61 33.03 2004.206 +114.0 -191.0 +118.0 -191.012 40 43.12 +46 26 55.4 17.00 18.93 257.23 11.51 2003.191 -26.0 -77.0 -31.0 -79.012 41 12.37 +50 38 18.7 15.54 17.41 138.10 13.05 2002.106 -72.0 +30.0 -74.0 +29.012 42 38.32 +61 21 24.4 18.31 19.00 147.56 6.35 2004.288 -73.0 -24.0 -65.0 -27.012 43 04.91 +10 10 02.5 12.41 16.11 27.18 35.12 2003.319 -119.0 -58.0 -129.0 -54.012 44 58.89 +42 48 13.2 15.59 18.00 70.37 22.60 2004.291 -103.0 -46.0 -102.0 -45.012 47 19.20 +02 29 39.4 14.81 16.99 83.76 18.93 2000.343 -104.0 -29.0 -104.0 -22.012 48 33.42 +04 08 36.7 13.17 17.03 319.90 40.62 2001.290 -86.0 -1.0 -86.0 -3.012 53 28.40 +36 12 30.4 14.38 14.99 278.19 14.98 2004.291 -79.0 +2.0 -77.0 +5.012 55 33.51 +26 27 25.8 14.65 17.52 177.98 21.99 2004.973 -76.0 -40.0 -74.0 -39.012 55 46.88 +05 00 23 16.01 18.94 26.92 9.98 2001.290 -74.0 -20.0 -81.0 -19.012 56 39.38 +31 02 40.8 16.68 18.36 192.87 35.39 2004.362 +51.0 -85.0 +50.0 -83.012 59 54.49 +36 20 06.2 14.93 17.67 168.60 13.21 2004.130 -16.0 -105.0 -14.0 -104.013 00 54.03 +09 39 39.9 15.39 16.22 171.01 24.38 2003.319 +36.0 -124.0 +34.0 -121.013 02 51.78 +32 37 55.4 11.86 18.25 96.21 56.30 2004.362 -69.0 +14.0 -70.0 +12.013 03 27.85 +42 50 09.9 16.10 18.94 170.00 43.17 2003.313 -59.0 +95.0 -54.0 +91.013 05 11.27 +06 54 54.6 15.76 17.58 153.05 7.51 2003.248 -77.0 -12.0 -71.0 -21.013 07 34.85 -02 45 07.6 15.71 18.91 278.63 44.45 2000.171 +8.0 -76.0 +10.0 -85.013 08 15.79 +08 12 46.8 17.36 18.16 329.73 11.82 2003.248 -17.0 -85.0 -18.0 -88.013 09 03.20 +35 54 40 12.75 16.49 196.01 93.60 2004.207 -79.0 -89.0 -75.0 -89.013 10 21.34 +32 52 58.6 14.37 17.19 359.92 66.43 2004.362 -175.0 +1.0 -178.0 0.013 10 39.43 +07 14 20.9 15.63 15.99 301.59 23.34 2003.248 -77.0 -58.0 -81.0 -62.013 10 53.48 +54 39 25.6 14.47 17.90 344.27 8.50 2002.287 -70.0 -9.0 -73.0 -3.013 11 21.11 +58 56 13.4 14.23 16.54 234.86 34.08 2002.120 -73.0 -9.0 -70.0 -5.013 13 39.49 +59 14 25.4 13.80 18.85 289.88 16.15 2002.120 -70.0 -27.0 -68.0 -29.013 14 26.82 +17 32 09.2 16.29 18.50 341.15 19.96 2004.393 -40.0 -58.0 -41.0 -58.013 14 46.90 +25 44 26.3 16.52 18.03 110.07 8.56 2004.973 -97.0 0.0 -89.0 -2.0Table continued on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 67351 New Common Proper-Motion Pairs from the Sloan Digital Sky SurveyRA DEC (2000) Mags Angle Separation DATE PM-A PM-B13 16 14.32 +15 56 28.3 13.21 15.77 273.37 19.37 2005.416 -73.0 -17.0 -72.0 -13.013 16 37.70 +12 43 37.8 15.23 18.19 141.02 62.17 2003.223 -87.0 -4.0 -86.0 +3.013 17 45.23 +00 32 52.1 14.36 15.92 24.60 35.81 2004.447 -105.0 -34.0 -103.0 -35.013 19 46.52 +53 57 51.9 14.52 16.06 170.95 16.04 2002.287 -34.0 -74.0 -32.0 -74.013 21 56.02 +23 04 43.7 14.18 16.04 304.59 30.88 2005.252 -75.0 -2.0 -73.0 -1.013 22 15.77 +05 31 17.7 15.05 17.70 236.54 46.92 2001.214 +26.0 -137.0 +25.0 -137.013 23 58.43 +10 29 23 16.00 16.56 169.77 21.35 2003.322 -86.0 -101.0 -80.0 -92.013 25 18.32 +15 14 17.4 15.88 16.88 142.31 21.91 2004.075 +56.0 -44.0 +54.0 -47.013 25 36.98 +43 44 37.6 16.46 16.83 165.70 9.69 2003.226 -5.0 -77.0 -4.0 -81.013 26 59.36 +02 29 41.5 15.89 18.55 176.52 15.89 2000.343 -151.0 -40.0 -159.0 -40.013 33 04.16 +38 13 07.6 15.70 18.34 233.12 9.11 2003.316 -45.0 -67.0 -49.0 -64.013 36 02.47 +18 45 51.6 14.74 17.53 54.78 32.60 2004.710 -133.0 +28.0 -132.0 +26.013 40 10.74 +14 30 41.6 14.36 18.77 88.03 63.59 2004.075 -31.0 -64.0 -31.0 -63.013 46 30.50 +15 22 22 15.67 18.75 234.78 11.99 2005.359 -67.0 -26.0 -69.0 -30.013 49 53.35 +28 54 57.2 14.57 15.44 358.16 53.99 2004.713 +4.0 -94.0 +6.0 -99.013 53 00.71 +04 32 56 15.13 18.57 277.18 23.77 2004.729 -61.0 -75.0 -65.0 -78.013 54 03.88 +16 31 10.9 15.80 17.17 8.77 36.23 2005.359 -72.0 -29.0 -71.0 -27.013 54 51.71 +51 28 15.6 15.09 18.09 333.53 10.32 2002.248 -67.0 -44.0 -68.0 -41.013 57 48.38 +24 47 36.3 16.89 17.34 147.51 36.46 2004.447 -76.0 +24.0 -77.0 +24.013 58 34.98 -08 09 59.5 14.75 15.10 143.70 13.46 1994.637 -81.0 +63.0 -72.0 +60.013 59 15.99 +13 34 03.1 15.28 15.69 206.47 22.44 2004.075 -77.0 -15.0 -75.0 -10.014 03 41.15 +14 40 55.7 15.40 18.38 358.61 54.76 2005.364 -64.0 +46.0 -60.0 +48.014 05 54.78 +19 29 40.2 17.68 18.89 17.15 7.47 2005.195 -60.0 +38.0 -65.0 +41.014 08 23.52 +11 40 03 18.24 18.95 248.65 36.79 2003.314 +58.0 -91.0 +58.0 -97.014 09 37.83 +13 49 15.4 15.17 17.75 235.33 19.16 2003.409 -81.0 +4.0 -82.0 -4.014 10 48.81 -03 05 21.1 14.16 15.47 315.00 18.08 2001.394 -93.0 -65.0 -90.0 -59.014 12 32.44 +07 17 46.1 14.49 17.28 355.59 11.82 2003.319 +65.0 -104.0 +69.0 -100.014 13 28.70 +23 31 12.7 14.11 17.27 299.23 11.37 2004.450 -72.0 -52.0 -70.0 -52.014 15 34.71 +48 06 42.1 14.49 16.66 163.61 40.35 2003.324 -77.0 -12.0 -79.0 -9.014 16 41.14 +32 32 28.1 14.13 17.35 291.05 10.42 2004.288 -27.0 +99.0 -31.0 +105.014 17 57.35 +07 25 35.1 16.07 18.11 148.32 18.20 2001.457 -76.0 +41.0 -81.0 +39.014 18 34.18 +17 20 00.2 14.46 18.44 295.97 56.58 2005.356 +113.0 -17.0 +120.0 -20.014 19 46.72 -02 30 22 18.64 18.76 109.57 35.15 2001.454 -81.0 -40.0 -76.0 -39.014 19 56.10 +16 33 37.2 15.13 16.10 267.34 63.24 2005.353 -83.0 +23.0 -87.0 +21.014 21 53.99 +00 18 08.3 14.81 15.67 266.75 32.57 1999.221 -77.0 -8.0 -73.0 -7.014 23 39.16 +04 07 29.7 13.92 16.06 300.98 16.20 2001.214 +36.0 -111.0 +30.0 -117.0Table continued on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 69351 New Common Proper-Motion Pairs from the Sloan Digital Sky SurveyRA DEC (2000) Mags Angle Separation DATE PM-A PM-B15 29 14.80 +50 26 31 12.86 15.55 204.79 69.70 2002.437 -61.0 +37.0 -63.0 +36.015 29 24.12 +17 34 27.8 15.06 18.96 72.40 48.78 2005.356 -95.0 -61.0 -100.0 -55.015 34 58.77 +20 35 28.6 17.61 18.88 110.15 7.44 2004.392 -75.0 -34.0 -73.0 -32.015 35 20.98 -00 17 51.2 12.09 16.67 219.97 30.08 1999.218 +44.0 -83.0 +46.0 -86.015 41 49.74 +26 47 06 15.57 18.25 33.32 13.27 2004.209 -94.0 -4.0 -89.0 -7.015 43 19.30 +40 24 09.6 16.17 18.07 315.77 36.80 2005.359 +16.0 -135.0 +17.0 -136.015 45 00.78 +19 32 54.8 17.76 18.67 163.53 15.15 2004.392 -77.0 -14.0 -77.0 -21.015 45 05.80 +09 23 16.1 17.13 18.81 137.85 53.78 2003.472 -85.0 +4.0 -86.0 +10.015 47 05.72 +01 45 47.9 15.00 18.71 286.04 68.35 2000.341 -81.0 -4.0 -75.0 -7.015 48 17.61 +37 05 52.3 16.06 17.73 109.26 37.83 2003.407 +19.0 -69.0 +23.0 -73.015 50 42.54 +03 01 43.8 15.67 17.58 349.56 24.65 2001.214 -54.0 -92.0 -53.0 -89.015 56 09.50 +03 21 48.7 17.80 18.90 142.31 27.76 2001.214 -70.0 -38.0 -73.0 -39.016 04 33.30 +09 54 06.2 16.23 18.80 54.04 20.69 2005.362 +25.0 -69.0 +30.0 -70.016 07 15.16 +34 57 53.9 14.89 17.22 168.82 67.06 2003.406 -32.0 +83.0 -29.0 +76.016 11 42.15 +10 22 26.2 13.12 17.61 91.07 15.16 2005.354 +46.0 -144.0 +51.0 -144.016 13 40.56 +39 34 55.1 14.84 18.48 155.01 28.62 2002.353 -69.0 +37.0 -64.0 +30.016 14 16.06 +42 15 29.5 15.81 17.99 69.76 24.68 2002.438 -113.0 +70.0 -107.0 +69.016 17 09.40 +44 06 47 13.77 16.69 16.17 56.82 2001.375 -35.0 +94.0 -38.0 +93.016 27 23.60 +43 36 19.6 15.55 17.98 77.31 16.17 2001.392 -94.0 +51.0 -98.0 +58.016 31 49.00 +38 04 52.3 17.07 18.74 249.62 26.00 2002.438 +2.0 +84.0 -1.0 +77.016 34 42.40 +22 31 41.4 12.55 18.48 251.85 39.85 2003.330 +5.0 -76.0 +1.0 -71.016 42 25.62 +19 08 06 18.82 19.46 333.79 6.38 2003.317 -83.0 +4.0 -84.0 -2.016 58 09.95 +26 52 27.1 12.76 17.44 272.40 18.42 2002.353 -83.0 -132.0 -88.0 -134.016 58 54.11 +49 42 51 12.92 17.80 53.74 23.18 2004.455 -34.0 +74.0 -33.0 +82.017 00 30.24 +33 13 37.1 16.23 17.06 289.30 27.11 2001.392 -46.0 -65.0 -47.0 -66.017 16 05.66 +63 06 21.4 13.63 15.86 10.63 31.30 1994.952 -11.0 -81.0 -8.0 -81.017 19 45.36 +67 22 58.6 13.19 15.83 219.07 22.95 2001.457 +27.0 -69.0 +28.0 -68.017 22 42.87 +71 47 18.1 15.44 18.75 160.08 10.34 2001.720 -13.0 +89.0 -6.0 +87.017 27 00.41 +33 06 03.4 14.91 18.58 312.00 39.90 2004.453 +7.0 -71.0 +12.0 -75.017 48 35.08 +46 05 51.2 16.23 18.73 34.33 19.83 2001.717 -2.0 +83.0 +1.0 +80.017 50 51.17 +49 42 51.9 14.80 15.68 189.73 14.05 1995.122 -35.0 +69.0 -30.0 +66.017 57 07.61 +43 03 26.3 15.18 15.34 111.28 35.84 2005.435 -9.0 -79.0 -7.0 -76.017 58 34.35 +23 48 21.7 15.60 17.29 265.19 19.81 2004.707 -1.0 -70.0 -8.0 -72.019 14 39.93 +37 17 21.5 13.41 16.82 64.86 47.81 2005.444 +28.0 -96.0 +25.0 -103.019 16 53.01 +37 14 12.7 14.42 17.42 177.54 28.52 1995.541 -34.0 +93.0 -31.0 +92.019 58 24.50 +60 31 54.1 13.69 18.96 246.17 51.55 1994.651 0.0 +96.0 -1.0 +95.0Table concludes on next page.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 70351 New Common Proper-Motion Pairs from the Sloan Digital Sky SurveyRA DEC (2000) Mags Angle Separation DATE PM-A PM-B20 08 28.93 +60 23 54.3 16.19 16.59 355.44 74.14 1994.651 -78.0 -30.0 -81.0 -27.020 09 31.23 +31 47 45.6 15.41 17.65 278.99 28.35 2003.317 -29.0 -81.0 -28.0 -83.020 33 58.01 +15 42 56.4 14.54 15.53 190.26 50.33 2004.783 +80.0 +41.0 +81.0 +45.020 36 44.74 +04 47 07.4 16.44 17.40 234.41 20.45 2005.742 -44.0 -63.0 -51.0 -68.020 47 11.39 +00 21 27.6 17.17 18.20 43.31 49.82 2003.324 -6.0 -101.0 -8.0 -95.021 00 11.29 +74 32 23.8 13.57 15.76 285.05 48.56 2003.740 -76.0 +24.0 -77.0 +19.021 20 56.07 +20 50 15.2 12.37 17.99 327.06 25.51 1994.643 +75.0 +18.0 +75.0 +17.021 38 58.41 -00 01 37 14.10 18.89 263.41 80.42 2001.788 +16.0 -91.0 +20.0 -88.021 41 56.72 +19 49 09 14.13 14.92 123.47 64.81 2004.712 -64.0 -32.0 -64.0 -34.021 43 10.20 +13 49 53.1 17.66 18.47 304.46 13.51 1994.643 -44.0 -66.0 -47.0 -62.021 48 59.56 +13 03 32.6 15.47 16.13 236.64 20.77 2000.740 -85.0 -22.0 -86.0 -24.021 55 17.40 -00 46 23.4 15.56 15.71 0.52 35.43 2002.777 +61.0 -53.0 +62.0 -52.022 03 36.37 +43 58 59.5 14.58 18.79 86.35 13.30 1994.652 +146.0 +49.0 +151.0 +48.022 04 48.64 +22 26 28.4 17.41 17.70 40.96 35.49 2004.784 -107.0 -55.0 -109.0 -53.022 19 38.34 +22 58 38.1 13.72 17.37 2.57 48.55 2004.712 -69.0 -43.0 -66.0 -49.022 20 25.33 +05 19 56.9 16.92 18.56 271.33 31.54 2005.742 -111.0 -118.0 -114.0 -123.022 31 44.75 +13 19 23.9 17.02 18.69 298.25 10.54 2000.740 -13.0 -74.0 -14.0 -75.022 36 16.06 +21 51 12.4 15.54 17.44 293.61 46.73 2003.738 +106.0 -79.0 +101.0 -77.022 36 59.49 +01 07 44.4 16.38 16.72 144.25 23.84 2001.788 +52.0 -47.0 +55.0 -50.022 38 58.94 +68 27 39.6 14.54 14.99 37.63 72.57 2003.738 +75.0 -8.0 +76.0 -13.022 42 31.14 +12 50 04.9 16.36 16.62 257.73 12.13 2003.738 -33.0 -76.0 -34.0 -73.022 52 15.78 +29 03 23.4 16.97 17.84 107.50 19.86 1994.949 -52.0 -52.0 -52.0 -51.023 19 26.03 +15 38 17 16.89 18.72 82.08 13.21 2000.740 -29.0 -81.0 -29.0 -79.023 19 53.22 -01 05 25.4 16.18 18.75 323.95 23.39 2002.678 -48.0 -78.0 -48.0 -75.023 28 43.52 +07 03 10.6 12.79 15.36 74.08 97.65 2004.707 +152.0 -28.0 +147.0 -36.023 54 35.23 +24 27 45.6 15.63 16.70 124.05 14.40 2004.712 +87.0 -29.0 +88.0 -27.023 59 54.91 -04 12 12.9 16.48 17.09 150.94 77.06 1994.952 -53.0 -96.0 -52.0 -97.0Table Notes:• Data taken from the SDSS-DR7 survey.• The position angle is in degrees, the separation in arcseconds, and the proper motion in millisecondsof arc/year.

Vol. 8 No. 1 January 1, 2012Journal of Double Star ObservationsPage 71Journal of Double Star ObservationsJanuary 1, 2012Volume 8, Number 1EditorsR. Kent ClarkRod MolliseEditorial BoardJustin SandersMichael BolemanAdvisory EditorBrian D. MasonThe Journal of Double Star Observations isan electronic journal published quarterly bythe University of South Alabama. Copies canbe freely downloaded fromhttp://www.jdso.org.No part of this issue may be sold or used incommercial products without written permissionof the University of South Alabama.©2012 University of South AlabamaQuestions, comments, or submissions may bedirected to rclark@jaguar1.usouthal.eduor to rmollise@bellsouth.netThe Journal of Double Star Observations (JDSO)publishes articles on any and all aspects of astronomy involvingdouble and binary stars. The JDSO is especiallyinterested in observations made by amateur astronomers.Submitted articles announcing measurements, discoveries,or conclusions about double or binary stars may undergoa peer review. This means that a paper submittedby an amateur astronomer will be reviewed by other amateurastronomers doing similar work.Not all articles will undergo a peer-review. Articlesthat are of more general interest but that have little newscientific content such as articles generally describingdouble stars, observing sessions, star parties, etc. will notbe refereed.Submitted manuscripts must be original, unpublishedmaterial and written in English. They should contain anabstract and a short description or biography (2 or 3 sentences)of the author(s). For more information about formatof submitted articles, please see our web site atwww.jdso.orgSubmissions should be made electronically via e-mailto rclark@jaguar1.usouthal.edu or to rmollise@bellsouth.net.Articles should be attached to theemail in Microsoft Word, Word Perfect, Open Office, ortext format. All images should be in jpg or fits format.We’re on the web!http://www.jdso.org