With sapphire waterfalls, lava rain and orbits around dead stars, these distant worlds push the limits of what’s possible.

Artist's impression of the newly named exoplanet Isagel (right) that orbits the star Aniara (HD 102956) in the Big Dipper 399 light years from Earth. The planet is about as massive as Jupiter and ...

If you step back in time, thousands of years ago, people knew about the brightest planets pretty much everywhere. These are Mercury, Venus, Mars, Jupiter and Saturn. And pretty much every culture knew ...

It's estimated there may be trillions of rogue planets wandering through the Milky Way, unbound to any star. Since detecting our first ones, we have been presented with an odd mystery.

Astronomers just measured the mass of a free-floating planet without a star for the first time ...

This transcript was prepared by a transcription service. This version may not be in its final form and may be updated. Danny Lewis: Almost 800 million miles away from Earth, the moon Enceladus orbits ...