A rare observation opportunity revealed the presence of a thin atmosphere around a small object beyond Pluto.

If confirmed, the rock would become just the second world past Neptune in our solar system to host an atmosphere.

The finding comes with significant new suggestions about the solar system ...

A tiny world in our Solar System has an atmosphere it shouldn’t—hinting something dramatic happened there recently.

Astronomers have spotted something surprising in the far outer Solar System—a faint, short-lived atmosphere clinging to a tiny icy world that shouldn’t be able to hold one at all. The object, called ...

Pluto was believed to be the only body beyond Neptune with an atmosphere. Now, a new discovery in our solar system is challenging that assumption.

The atmosphere is between 5 million and 10 million times thinner than Earth's atmosphere. A very small body, far from the sun in an icy outer realm of the solar system, has mysteriously grown an ...