Spacecraft Parts

The spacecraft has several major subsystems, almost all of which have backups (redundant systems) to ensure mission success just in case the first one fails. Mars Reconnaissance Orbiter was designed to be "single fault tolerant," meaning that if any one item fails, the spacecraft would still be able to complete the mission. This high level of reliability was very important since, once it was launched, Mars Reconnaissance Orbiter was forever out of reach of a service call!

Some of the most important parts of the spacecraft are the:
	Instruments:	tools for conducting science and other research experiments
Other major spacecraft subsystems include:
	Structures:	for holding all of the engineering and science equipment
	Mechanisms:	for allowing some parts to point independently of the main spacecraft
	Telecommunications:	for radio communications between Earth and the spacecraft
	Antennas:	for sending and receiving data
	Propulsion:	for correcting the spacecraft's flight path and getting into Mars orbit
	Command and Data-Handling Systems:	for storing and processing data and commands
	Guidance, Navigation, and Control Systems:	for helping to guide the spacecraft to Mars and for keeping it oriented correctly
	Thermal Systems:	for maintaining proper temperatures in the extreme environment of space
	Electrical Power:	for providing electricity to the spacecraft