like Earth's moon, orbit another planet in the Solar System. This strengthened his belief that the claim previously published by Nicolaus Copernicus was correct, according to which it was not Earth ...

On Earth, you can look up at night and see the Moon shining bright from ... which keeps all of the planets in orbit. The Sun is the most massive object in our solar system, which means it has ...

But is our moon actually a planet? The answer is technically ... can be to define terms in astronomy," Grayson said. "Most things in the universe exist not in neat boxes but rather on a spectrum ...

Mars will seem to disappear behind the full wolf moon Monday for many sky-gazers. Throughout January, also look up to see ...

Explore the universe with news on fascinating ... how Pluto acquired its unusually large moon Charon, which is about half the size of the dwarf planet. Now, new research suggests that Pluto ...