Compass-1 (also known as Compass One) is a German amateur CubeSat picosatellite, built and operated in the late 2000s by Aachen University of Applied Science. It was launched by the Indian Space Research Organisation, aboard a PSLV rocket as a secondary payload to the CartoSat-2A primary spacecraftHerbert J. Kramer, "eoPortal Directory-Compass-1", eoPortal Directory, retrieved 05-08-17 on 28 April 2008. It was launched into a Geocentric orbit with an altitude of 597 km.Heavens Above, "Heavens Above", COMPASS-1 Orbit, retrieved 05-08-17 Its primary mission is remote sensing; however, it also contains some technology demonstration experiments regarding the use of small satellites and GPS tracking.
On 10 August 2008, the satellite developed a problem and switched into "emergency mode". Initial attempts to rectify this problem failed; however, normal operations were resumed on 10 September, with help from amateur radio operators around the world.
Overview
Most of the objectives for Compass-1 were focused on the evaluation and testing of CubeSats and new technologies. It was made using scratch-built software, hardware, and parts, except the solar panels. Thus it inherited a high risk for mission failure.FH Aachen, "Overview", COMPASS-1, retrieved 05-08-17
Mission Objectives
Mission objectives include:
-Take color pictures in 640 by 480 resolutionFH Aachen, "Overview-Mission Objectives", COMPASS-1, retrieved 05-08-17
-Validate a Phoenix GPS receiverFH Aachen, "Overview-Mission Objectives", COMPASS-1, retrieved 05-08-17
-Test a Magnetic Actuator based 3-axis gyroscopeFH Aachen, "Overview-Mission Objectives", COMPASS-1, retrieved 05-08-17
Mission Anomalies
There have been events that have been solved but remain to be explained, as Compass-1 has entered emergency mode and has undergone full resets a number of times.
Emergency Mode
August 10, 2008 On August 10, 2008, Compass-1 entered Emergency mode. The cause was unknown and FH Aachen put out a call to all amateur radio operators to try to find out what was going on with the CubeSat. A hard reset occurred, only to bring the satellite into a circle of powering up, turning on the heaters, and then dying again.Från ANS kommer, "COMPASS-1 CubeSat in Emergency Mode", AMSAT-AM, 08-17-08 The only way to exit this loop was to avoid starting the heaters. The team needed as much Telemetry from the ground as possible, which was from amateur radio enthusiasts.
September 10, 2008
After multiple tries, the Compass-1 team finally got enough charge retained in the batteries to boot the CubeSat and get a beacon and images back from the probe.Herbert J. Kramer, "eoPortal Directory-Compass-1", eoPortal Directory, retrieved 05-08-17 It was later determined that there was a major software flaw that prevented the heaters from letting the battery charge.
Hard Resets
There have been multiple hard resets, with the most recent one being on February 8, 2009.DK3WN "Compass-1 now in powersafe mode","DK3WN SatBlog"
End of life
Compass-1 was retired on March 3, 2012. It still can be used as a beacon until it burns up or the batteries can no longer hold charge. It is expected to stay in orbit until 2019.DK3WN "COMPASS-1 still listening …","DK3WN SatBlog"
See also CUTE-1.7 Delfi-C3 AAUSAT-II List of CubeSats COMPASS-2
References
External links Compass-1 Official Site Compass-1 forum