They were right. Today there are five known dwarf planets in the Solar System. The conditions for what classifies a “planet” as opposed to a “dwarf planet” were set by the International ...

New images from the JWST are about as close as we've ever come to seeing the sky of an alien world outside the Solar System.

All of our solar system’s planets are lining up to parade through the night sky at once. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known ...

Astronomers have discovered a rare in-sync solar system with six planets moving like a grand cosmic orchestra, untouched by outside forces since their birth billions of years ago. The find ...

A European-Japanese spacecraft has beamed back some of the best close-up photos yet of Mercury's north pole as part of only ...

Astronomers using planet-hunting satellites have discovered a rare solar system with six planets moving completely in sync with one another, as if they were untouched by any outside force since ...

at least five dwarf planets, tens of thousands of asteroids, and around three trillion comets and icy bodies. Although not all objects of the solar system are as well known as Earth, Jupiter ...

Check out the rest of the series. If you were born in the last century you might have memorized that there were nine planets in our solar system, as heard in the famous Schoolhouse Rock!