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125
ASTEROIDS OBSERVED FROM GMARS AND SANTANA
OBSERVATORIES: 2009 JANUARY - FEBRUARY
Robert D. Stephens
Goat Mountain Astronomical Research Station (GMARS)
11355 Mount Johnson Court, Rancho Cucamonga, CA 91737
RStephens@foxandstephens.com
(Received: 2009 Apr 12)
Lightcurves for 654 Zelinda, 946 Poesia, and 1655
Comas Sola were obtained from Santana and GMARS
Observatories in 2009 January and February.
Observations at Santana Observatory (MPC Code 646) were made
with a 0.30-m Schmidt-Cassegrain (SCT) with a SBIG STL-
1001E. Observations at GMARS (Goat Mountain Astronomical
Research Station, MPC G79) were made with two telescopes, both
0.35-m SCT using SBIG STL-1001E CCD Cameras. All images
were unguided and unbinned with no filter. Measurements were
made using MPO Canopus, which employs differential aperture
photometry to produce the raw data. Period analysis was done
using Canopus, which incorporates the Fourier analysis algorithm
(FALC) developed by Harris (1989). The asteroids were selected
from the list of asteroid photometry opportunities published on the
Collaborative Asteroid Lightcurve Link (CALL) website (Warner
et al., 2008).
654 Zelinda. 654 Zelinda had a favorable opposition in 2009.
Images were obtained on February 11, 19, 20 and 21 with the
0.30-m SCT at Santana Observatory. All others were obtained
with the 0.35-m SCT at GMARS. Warner and Higgins (2008)
obtained a lightcurve in 2008 September, reporting a period of
32.0 ± 0.1 h. Schrober (1975) reported a period of 31.9 ± 0.05 h
with a U = 2 rating.
946 Poesia. Images on January 19 and 28, and February 3 and 4
were obtained with the 0.30-m SCT at Santana Observatory. All
others were obtained with the 0.35-m SCT at GMARS. The data
were linked to an internal standard using a method developed by
Warner (2007) and described by Stephens (2008) included in the
latest release of Canopus. No previously reported result has been
published.
References
Addleman, D., Covele, B., Duncan, A., Johnson, J., et al. (2005).
Minor Planet Bul. 32, 76-78.
Behrend, R. (2009). Observatoire de Geneve web site,
http://obswww.unige.ch/~behrend/page_cou.html
Harris, A.W., Young, J.W., Bowell, E., Martin, L.J., Millis, R.L.,
Poutanen, M., Scaltriti, F., Zappala, V., Schober, H.J., Debehogne,
H., and Zeigler, K.W. (1989). “Photoelectric Observations of
Asteroids 3, 24, 60, 261, and 863.” Icarus 77, 171-186.
Schober, H.J. (1975). Astron. Astrophys. 44, 85-893
Stephens, R.D. (2008). “Long Period Asteroids Observed from
GMARS and Santana Observatories.” Minor Planet Bul. 35, 31-
32.
Warner, B.D. (2007). “Initial Results from a Dedicated H-G
Project.” Minor Planet Bul. 34, 113-119.
Warner, B.D., Harris, A.W., Pravec, P. (2008). Asteroid
Lightcurve Parameters http://www.MinorPlanetObserver.com/
astlc/default.htm.
Warner, B.D. and Higgins, D. (2008). “Lightcurve Analysis of 654
Zelinda.” Minor Planet Bul. 35, 32-33.
654 Zelinda 946 Poesia
1655
Comas Sola
Dates 01/17–02/21 01/01–02/04 12/31-01/16
Data Pts 5,126 1,938 1,962
α 8.7, 22.2 6.5, 8.7 7.6, 15.4
Avg L PAB 123 116 88
Avg B PAB -14 1 -4
Per. (h) 31.735 108.5 20.456
PE (h) 0.01 0.5 0.004
Amp (mag) 0.12 0.32 0.22
AE (mag) 0.02 0.05 0.03
Table 1. Observing circumstances. Dates are in 2009, except for the
first observation of 1655, which was 2008.
1655 Comas Sola. Images on January 1 were obtained with the
0.35-m SCT at GMARS. All others were obtained with the 0.30-m
SCT at Santana Observatory. Addleman (2005) obtained a partial
lightcurve at Rose-Hulman Institute of Technology and reported a
period of 20.4 ± 0.1 h, in good agreement with this result. Behrend
(2009) reported a period of greater than 12 h.
Acknowledgements
Thanks are given to Dr. Alan Harris of the Space Science Institute,
Boulder, CO, and Dr. Petr Pravec of the Astronomical Institute,
Czech Republic, for their ongoing support of amateur asteroid
research. Also, thanks to Brian Warner for his continuing work
and enhancements to the software program MPO Canopus which
makes it possible for amateur astronomers to analyze and
collaborate on asteroid rotational period projects and for
maintaining the CALL Web site which helps coordinate
collaborative projects between amateur astronomers.
Minor Planet Bulletin 36 (2009)