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on the appropriate star map, and the timewas recorded. This was done every fiveminutes for the entire night. Nearly 100observations of the satellite were madeduring this night.While these observations were beingcarried out, the satellite’s flashing becameunusual. Instead offlashing brightlyonce every minute,every alternate flashwas growing dimmeras the nightprogressed. At theend of the observingsession only everyalternate flash wasvisible. What thistold us was thatMolniya 1-75 hadnot been tumblingonce every minuteas we had believed,but every twominutes since wewere seeing twodifferent sides of thesatellite.The data were used to update theorbital elements of the satellite in orderto find it again. On September 4, 1997,film images of Molniya 1-75 were collected.From 03:54 to 05:02 UT I obtained twelvephotos of the satellite and analyzed theseimages using my own astrometry software.The data collected were used to updatethe orbital elements of the satellite.It was obvious to us that analyzingfilm images of the satellite streaks wasan impractical exercise and that a moreefficient means of imaging was needed.In January 1998, SSRAL had learned of aMeade 10-inch reflecting telescope andan SBIG ST-6 CCD (Charge Coupled Device)digital camera that were not being used.SSRAL decided to acquire this equipmentfrom the Astronomy Lab at RMC to begintracking Molniya satellites using CCDtechnology. Unlike my telescope, theMeade 10-inch was stepper-motor drivenand could be controlled via a telescopecontroller assembly. The 10-inch Meadealso had 1.6 times the light-gatheringcapability of my 8-inch telescope. Thismeant that dimmer objects (such assatellites with higher ranges) could bedetected. There were many advantagesto using a CCD camera instead of film.The major one was its superior sensitivity.Another advantage over film was thatCCD images did not cost money to develop.The Meade 10-inch Schmidt-Cassegrain reflecting telescope is seen withthe equipment used to control it. This was the primary satellite trackingsystem used by SSRAL until its more advanced system went online onJanuary 29, 2000.The first SSRAL satellite trackingapparatus that employed a CCD camerawas used forthe first timeon February 6,1998 to trackthe satelliteMolniya 3-10.By coincidence,that satellitealso exhibitedbrightflashes. Morepractical CCDimages of anotherMolniyasatellite (1-75)were takenthree days later.Atotal of 24images of thesatellite wereacquired foranalysis. During that tracking run, thesatellite’s range had decreased from 38,000km to 13,500 km as the satellite headedfor its perigee. After the initial CCD successwith Molniya 1-75, SSRAL began an analysisof how sensitive the CCD camera was byexamining other Molniya satellites overmany viewing conditions. During thatanalysis, SSRAL obtained many imagesof those Molniya satellites that exhibitedflashes with periods much smaller thanthat of Molniya 1-75. SSRAL began doinga tumble analysis of every Molniya satelliteit found that exhibited flashes. The mostnotable at that time was Molniya 3-43.This satellite had been accidentally imagedby SSRAL during routine tracking of theMolniya 1-87 satellite. On April 12, 1998an all-night tracking session of the satellitewas undertaken to provide the data forthe most accurate tumble analysis of thatsatellite to date. A total of 159 images ofthe satellite were gathered during thatnight, yielding a total of 450 individualflashes. Using the data collected from theimages, the tumble period for Molniya3-43 was found to be about 4.5 seconds.Tumbling satellites exhibit variedlight curves since different sides of thesatellite are being illuminated as it tumbles.This could confuse the observer intobelieving that the satellite is tumbling ata faster rate than it actually is. To date,Molniya 1-87 was being tracked on March 17, 1998 when another satelliteappeared in the field of view. Later analysis confirmed this object as Molniya3-43. It is extremely rare that two Molniya satellites are seen in the same 11by 14 arcminute field of view. Molniya 3-43 is the most analyzed satellite asfar as tumble period is concerned because of its easily seen flashes and smallflash time. This was a 20-second exposure using the Meade 10-inch reflectorand SBIG ST-6 CCD camera at prime focus.fourteen other Molniya satellites havebeen found to flash and therefore couldhave their tumble periods determined.Décember/ decembre 2000 JRASC215