NASA's James Webb Space Telescope unfolds its giant mirror for last time ahead of Oct. 31 launch

Cats love to be boxed in—even when there's no box. Watch this cat naturally gravitate towards and sit inside a nonexistent box:

NASA's OSIRIS-REx spacecraft has begun its 1.4 billion-mile journey back to Earth — and it's carrying historic asteroid samples

The great lunar 'bake off' of knots and moon rocks — Commander's report: lunar day 13