In 1908, something exploded in the sky over Siberia with hundreds of times the energy of the Hiroshima bomb, flattening more than 2,000 square kilometres of forest. When scientists finally reached the site years later, they found no crater at all
A Colorado startup just raised $30 million on a quiet bet that astronauts won't actually be the ones building the moon's first permanent base — robots will get there first
Interstellar's most-discussed scene is treated as exotic science fiction, but the family-separation problem it dramatises is one of the more actively studied subjects in long-duration mission planning.