A Pint-Size Nuclear Reactor Could Keep Lights On in Space. Defense Researchers Are Funding a Test.

DARPA has given SpaceNukes an agreement to build and nuclear-test a small "kilopower"-class reactor with Los Alamos, per a single trade listing; cost, power rating and test date are unconfirmed.

TL;DR

Anything people build in space, from a Moon base to a ship bound for the outer planets, eventually runs out of sunlight, and a reactor small enough to launch is the leading answer. DARPA, the defense research agency, has now signed up SpaceNukes to design, build and actually run a small "kilopower"-class fission reactor in a nuclear ground test with Los Alamos National Laboratory, according to a trade listing. It is the second funded ground test of a space reactor this fall and the third government-backed reactor effort on the books, after NASA's Mars ship and its Moon reactor. Nothing has flown, and no cost, power level or test date has been given. But the number of teams that are building real hardware, rather than drawing it, keeps growing, and that is how a power source goes from paper to the launch pad.

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