Simplesat Optical Microsatellite

Time period

September 1996 to January 2002

Project description

The Simplesat optical microsatellite is an engineering experiment. The experiment will determine if a small spacecraft can be deployed in space at a fraction of the cost of traditional systems of similar capabilities. The payload is a 12-inch (30.5-centimeter) diameter astronomical telescope. The satellite is carried aboard the space shuttle and, once in orbit, it is ejected and operates completely independently. The spacecraft has its own power, communications, and attitude control systems.

The satellite passed environmental testing and was loaded into a Get-Away-Special (GAS) canister early in 2001. Simplesat was carried into orbit aboard the Orbiter Discovery on August 10, 2001. Simplesat had a flawless ejection and began orbiting Earth.

Unfortunately, the ground station was never able to make radio contact with Simplesat after seperation from the Orbiter Discovery. Because of radio frequency overlap issues, the spacecraft was not allowed to broadcast a signal; Simplesat could only send a return signal after it had received a signal from the ground station. This issue was not resolved and Simplesat reentered the atmosphere in January 2002.

For more information on Simplesat, check its Web site http://ltpwww.gsfc.nasa.gov/simplesat.

Challenges and lessons learned

While designing the mechanical hardware for Simplesat, we had our first experiences with systems engineering. Learning how subsystems interact and affect one another and how to balance design compromises through an entire system has been very useful in subsequent projects.