Earth has a number of mini-moons and quasi-moons. Mini-moons are objects that orbit our planet. But they make for fickle fans: They tend to swing around Earth for only a matter of months. One example ...

Every year, the moon, Earth's reliable celestial companion for 4.5 billion years, is getting 1.5 inches away. The distance to ...

Titan's shadow will fall on Saturn in the early hours of Sept. 20, one day before the world shines at opposition in Earth's ...

Much as we may treasure and proclaim our independence, we actually live in a protective bubble called the heliosphere.