as its Galilean moons show off while they dance in their orbits around the gas giant. Tonight, Europa and Ganymede transit Jupiter together, as they have a few other times this month. However ...

Astronomers have traced the origin of asteroid 2024 YR4, which appears to have broken off from a larger space rock.

“Why, a moon is a celestial body that orbits a planet,” you’re probably thinking. Well, sure—if you squint your eyes and don’t look too closely, that’s a pretty decent descriptio ...

This striking satellite footage shows the moon's shadow racing across North ... This spacecraft is geostationary, meaning that it orbits Earth at the same speed as the planet spins, allowing ...

A report by the New York Times said these moons were possibly formed by “cosmic smashups” that sent debris into Saturn’s orbit about 100 million years ago. “Many of these moons are rocks ...

Tianwen-4 is scheduled to launch around 2029 and head to Jupiter and eventually enter orbit around the Galilean moon Callisto. Next, a “ground simulation device for planetary habitable ...

The innermost moon, Phobos, has lots of craters and is roughly 13.8 miles (22.2 km) in diameter. In about 50 million years, it is expected to break up or crash into Mars. Deimos orbits 2.5 times ...

Even more exciting is the Jovian moon Io, the Galilean moon closest to the giant planet. There, as many as eight or nine volcanoes are erupting at any one time. In fact, January 1980 was the only ...

The orbits would be highly eccentric ... The attractive force due to the moon is always greatest on the side of the earth nearest to it, and least on that farthest away, while its value at ...

Observers describe these bodies as irregular moons because they move along tilted orbits and often circle Saturn backward. Many are no more than a few miles across. Some are so faint that astronomers ...