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.

For decades, our solar system was thought to have nine planets, with Pluto considered the smallest and farthest. But in 2006, ...

A newly detected planet beyond Pluto is not just expanding our understanding of the Solar System, it might be quietly rewriting it. Astronomers from the University of Taiwan recen ...

Almost 20 years after Pluto was infamously downgraded from its status as a planet, scientists now believe they have ...

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

A recent study found that Jupiter was once twice the size that it is now, making it big enough to swallow up 2,000 Earths.

Are planets in the solar system that are closer to the Sun older than the ones further away? – Gavriel, age 10, Paducah, Kentucky A cloud of collapsing gas created our Sun, the first thing to ...