New research suggests the moons of Jupiter and Uranus may hint that our planetary neighborhood once had a third ice giant.

The outer solar system once seemed like a quiet backwater. But a glut of tiny, strange moons with unruly orbits are coming ...

There’s no mistaking Jupiter in the sky these winter evenings, rising in the southeast as evening twilight ends. In fact, you should be able to easily see it long before twilight fades. Jupiter is by ...

We already know a decent amount about how planets form, but moon formation is another process entirely, and one we're not as familiar with. Scientists think they understand how the most important moon ...

You’ll want eyes on Jupiter this evening as Europa passes north of Callisto while Ganymede’s large shadow transits the gas giant’s cloud tops. Start observing by 11 P.M. EDT, as the bright planet ...