Snagged by Earth's gravity during an unusually close approach, this "minimoon" is predicted to orbit our planet for just 57 days; on Nov. 25, the asteroid will break free of Earth's influence and resume its regular orbit of the sun without a chaperone,

Asteroids are ripe for mining. Some contain gold or platinum. Others could help make rocket fuel. When they're mini-moons, that's a prime opportunity.