Satellites orbit objects like planets to perform various missions. They have orbits that are either geostationary, asynchronous, or polar. Rockets are used to launch satellites into orbit and have multiple stages powered by liquid or solid propellant engines. The first stage provides maximum thrust at launch while subsequent stages have lower thrust and place the satellite into its proper transfer orbit using liquid or cryogenic engines before the final apogee kick motor releases it onto its mission orbit. Precise propulsion, communication, electrical power, and computer systems are required for successful satellite launch and operation in space.