For the dwarf planet candidate, one trip around the sun takes over 24,000 years. Its orbit challenges a proposed path for a hypothetical Planet Nine.

NASA's latest discoveries about Jupiter have revealed astonishing new insights into the largest planet in our solar system.

There’s a new object in the distant reaches of our solar system, and it might just offer clues to a long-standing cosmic ...

Discover the order of planets in the solar system. From Mercury to Neptune, explore our solar system and learn more about our cosmic home. The solar system is our cosmic neighborhood, made up of ...

Astronomers find evidence of a possible ninth planet beyond Neptune, reigniting the debate about the formation of the Solar ...

Today, it’s believed that Jupiter and Saturn, the largest planets, were the first to fully form, both within a few million ...

The hypothesis suggested a larger, unseen Planet X lurks even further out on the edge of our solar system. Watch this: NASA taps SpaceX, Boeing to bring space travel back under America's wing 06: ...

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!

One set of dots had matching colors and brightness. open image in gallery Is there a possible ninth planet in our solar system? Researchers say they may have found a candidate (Credit: ESO/Tom ...

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar ...