Nuclear Powers Space Missions

Space missions have helped us learn about the planets, stars, and even the edges of our solar system. Spectacular pictures and scientific data have painted a detailed pictured of not only what our galaxy looks like but also what its made of.

The technology used to provide electric power to capture and transport this information from outer space to Earth has been around since 1961. Back then government scientists first used radioisotope thermoelectric generators (RTGs) with the launch of a U.S. Navy transit navigation satellite, similar to today's global positioning satellite system installed.

Now RTGs are helping Cassini-Huygens, the spacecraft and probe, launched in 1997 explore Saturn and one of its moons Titan. According to scientists, Titan's atmosphere is similar to that of young Earth. More information sent back from Titan could tell us if it is able to support some form of life. Powered by only three RTGs, which is the equivalent of nine 100 watt-light bulbs, Cassini-Huygens spacecraft has enough electrical energy to power not only all the equipment on-board but also take and send back pictures and data from the Saturn system even after its 2008 mission end date.

RTGs have been involved in more than 25 space missions providing power in deep space for Voyager 1 and 2, several Apollo missions, Galileo, Nimbus and LES, and many others. The requirements for power in space are specific to the remote and harsh conditions they operate in. The generator must meet the missions power needs and space limitations plus the unit must be reliable enough to work without moving parts which may fail or wear out years later. RTG's have proven to be the best option to date especially where solar panels cannot supply enough power.

With contributions from Shannon Bragg-Sitton