Sedna will make its closest approach to the Sun in 2076, giving us a rare opportunity to visit the planetoid before it drifts ...

Pluto was long considered our ninth planet, but the International Astronomical Union reclassified Pluto as a dwarf planet in ...

How many dwarf planets are there in our solar system? The recent discovery of 2017 OF201 makes the tally anywhere between ...

The James Webb Space Telescope (JWST) has discovered that a hazy sky over frozen Pluto is helping to cool the dwarf planet's atmosphere, while at the same time giving methane and other organic ...

How long does it take Pluto to orbit the sun? Learn more about how this planet makes one lap around our Solar System.

What processes during the formation of Pluto's largest moon, Charon, potentially led to it having cryovolcanism, and even an ...

Think you know Pluto? Think again. From its mysterious orbit to why it’s so hard to spot - even with Hubble - this video ...

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.

OF201, the object belongs to the same all-star family as Pluto: dwarf planets. Its diameter, roughly 435 miles (700 km), is half Pluto’s, ...

Close stellar encounters could change the structure of our planetary system, potentially dooming Earth or other worlds to ...