Tracking the rotation speed of solid planets, like the Earth and Mars, is a relatively simple task: Just measure the time it takes for a surface feature to roll into view again. But giant gas planets ...

Somewhere deep below Saturn s cloud tops, the planet rotates at a constant speed. Determining this interior period of rotation has proven extremely complicated. Now, with new Cassini results, a team ...

Figuring out the day length of Earth is more complicated than you might imagine. While on average a day is 24 hours long, throughout the year the planet's rotation can speed up and slow down, with one ...

The smashups are thought to have occurred at least 100 million years ago, but the moons they created are new to astronomers. Share on Facebook (opens in a new window) Share on X (opens in a new window ...