Astronomers used a telescope in Hawaii to find a new object on the outer edges of our solar system, helping to fuel evidence of a long-standing theory about Planet Nine, or Planet X. For years, ...

What happens when a planet contains immense quantities of water but is far too hot for that water to remain liquid?

Planets smaller than Neptune but larger than Earth, with atmospheres saturated with water vapor due to extreme temperatures, are puzzling astronomers. Scientists have developed an improved model to ...

It's been one Neptunian year—or about 165 Earth years—since astronomers first observed the most distant planet from the sun.

PRINCETON, N.J. (CNN/CNN Newsource/WKRC) — A new planet was possibly discovered beyond the planet Neptune. Researchers from the Institute for Advanced Study's School of Natural Sciences have announced ...

Astronomers discovered a primordial cluster beyond Neptune in the Kuiper Belt. Stable, ancient icy bodies may reveal ...

Astronomers used a telescope in Hawaii to find a new object on the outer edges of our solar system, helping to fuel evidence of a long-standing theory about Planet Nine, or Planet X. For years, ...