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First nuclear reactor in space

First nuclear reactor in space
Who
SNAP-10A
What
First
Where
United States
When
03 January 1965
On 3 April 1965, the USA launched SNAP-10A into a polar orbit around the Earth. Designed to test concepts for remotely operated nuclear reactors, SNAP-10A began producing electricity at more than 600 W some 12 hours after launch. After 43 days of operation the reactor shut down due to an electrical component failure. The spacecraft is still in orbit, some 1,200 km above Earth, and is not expected to re-enter the atmosphere for around 4,000 years.