01
Major Subsystems
- Structures and mechanisms.
- Electrical power system.
- Thermal control.
- Command and data handling.
- Communications.
- Guidance, navigation, and control.
- Propulsion.
- Payload instrumentation.
02
Thermal Control
Spacecraft cannot rely on ordinary atmospheric convection. Heat is transferred primarily through conduction within the vehicle and radiation to the environment.
03
Attitude Determination and Control
A spacecraft must determine its orientation and produce torques to point instruments, antennas, solar arrays, or propulsion systems correctly.
- Reaction wheels.
- Control-moment gyroscopes.
- Thrusters.
- Magnetic torquers in suitable near-Earth environments.
- Star trackers, gyroscopes, sun sensors, and magnetometers.