On February 15, 2013, a small asteroid exploded over the city of Chelyabinsk, Russia. [‘On This Day in Space’ Video Series on Space.com] The shock wave from this explosion damaged thousands of ...

The Rulison test — conducted at a depth of 8,425 feet — was the deepest subterranean nuclear-bomb detonation conducted in U.S. history.

To protect Allied astronauts and spacecraft, U.S. commanders need to stage a preemptive strike on Russia’s atomic-armed ASAT missile before it can be launched into orbit.

Satellite imagery of secretive nuclear facilities reveals Beijing’s efforts to expand its arsenal, just as the last global guardrails on nuclear weapons vanish.