Ever since NASA's New Horizons sent back the first-ever photos of Pluto in 2015, the dwarf ... with another planetary body a little over 400 miles in diameter, roughly the size of Arizona from ...

but it's big and spherical enough to be classified as a dwarf planet, just under half the size of Pluto. It's also quite an interesting oddball. It's the only dwarf planet closer to the Sun than ...

The building blocks of life could have been delivered to Ceres by one or more space rocks from the outer asteroid belt.

The brown dwarf, not quite a ... For the sake of comparison, Jupiter's mass is equal to about 318 Earths. The gravitational tugs of orbiting planets can cause host stars to wobble in an almost ...

The “demoted” dwarf planet Pluto and its largest ... Our moon, for comparison, is about 27 percent of Earth’s size. (But that’s still closer to Charon and Pluto than other moon-planet ...

Move over Saturn! Scientists have found a ring around an unassuming mini-planet in our Solar System to debunk the theory that only giant planets can be so adorned. The planet, dubbed Haumea ...

The dwarf planet is a bizarre, cryovolcanic world. However, the organic deposits discovered on its surface so far are unlikely to originate from its interior. The organic material found in a few ...