If you examine our solar system’s giant planets, you’ll notice right away that they’ve all got moons—a lot of moons. While ...

If our Moon suddenly vanished, Earth would already face dramatic consequences. But replacing it with entire alien worlds ...

We’ve discovered thousands of exoplanets — but not a single confirmed exomoon. That doesn’t mean they aren’t out there. In ...

The team of astronomers behind the find suggested it could help us better understand planet and moon formation in our solar system and beyond the Milky Way. The team was able to make the first-ever ...

For the first time, scientists have directly detected molecules in a Frisbee of gas and dust swirling around an alien gas-giant planet. “I didn’t think this was possible,” says astronomer Sierra Grant ...

Mercury, Venus, Neptune, Saturn, Uranus and Jupiter will appear together shortly after sunset on Feb. 28 — but is this the "planet parade" we've been waiting for?