Compass-1 (also known as Compass One) is a German amateur

CubeSat A CubeSat is a class of miniaturized satellite based around a form factor consisting of cubes. CubeSats have a mass of no more than per unit, and often use commercial off-the-shelf (COTS) components for their electronics and structure. CubeSats ...

picosatellite A small satellite, miniaturized satellite, or smallsat is a satellite of low mass and size, usually under . While all such satellites can be referred to as "small", different classifications are used to categorize them based on mass. Satellites ca ...

, built and operated in the late 2000s by Aachen University of Applied Science. It was launched by the

Indian Space Research Organisation The Indian Space Research Organisation (ISRO; ) is the national space agency of India, headquartered in Bengaluru. It operates under the Department of Space (DOS) which is directly overseen by the Prime Minister of India, while the Chairman ...

, aboard a

PSLV The Polar Satellite Launch Vehicle (PSLV) is an expendable medium-lift launch vehicle designed and operated by the Indian Space Research Organisation (ISRO). It was developed to allow India to launch its Indian Remote Sensing (IRS) satellite ...

rocket as a secondary payload to the

CartoSat-2A Cartosat-2A is an Earth observation satellite in a Sun-synchronous orbit and the third of the Cartosat series of satellites. The satellite is the thirteenth satellite in the Indian Remote Sensing (IRS) satellite series to be built, launched by ...

primary spacecraft on 28 April 2008. It was launched into a

Geocentric orbit A geocentric orbit or Earth orbit involves any object orbiting Earth, such as the Moon or artificial satellites. In 1997, NASA estimated there were approximately 2,465 artificial satellite payloads orbiting Earth and 6,216 pieces of space debris ...

with an altitude of 597 km. Its primary mission is

remote sensing Remote sensing is the acquisition of information about an object or phenomenon without making physical contact with the object, in contrast to in situ or on-site observation. The term is applied especially to acquiring information about Earth ...

; 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 panel A solar cell panel, solar electric panel, photo-voltaic (PV) module, PV panel or solar panel is an assembly of photovoltaic solar cells mounted in a (usually rectangular) frame, and a neatly organised collection of PV panels is called a photo ...

s. Thus it inherited a high risk for mission failure.

Mission Objectives

Mission objectives include: -Take color pictures in 640 by 480 resolution -Validate a Phoenix

GPS The Global Positioning System (GPS), originally Navstar GPS, is a Radionavigation-satellite service, satellite-based radionavigation system owned by the United States government and operated by the United States Space Force. It is one of t ...

receiver -Test a Magnetic Actuator based 3-axis gyroscope

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. The only way to exit this loop was to avoid starting the heaters. The team needed as much

Telemetry Telemetry is the in situ data collection, collection of measurements or other data at remote points and their automatic data transmission, transmission to receiving equipment (telecommunication) for monitoring. The word is derived from the Gr ...

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

and get a beacon and images back from the probe. 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.

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.DK3W
still listening …"
"DK3WN SatBlog"

References

External links

Compass-1 Official Site

Compass-1 forum
{{Use British English, date=January 2014 Student satellites Spacecraft launched in 2008 CubeSats Satellites of Germany Picosatellites