Clouds on Neptune have all but vanished. That's a surprise since it's the farthest planet from the sun and gets only 1/900 of the sunlight we get on Earth.

The difference between the daily high temperature and the daily low in many parts of the world is shrinking. Clouds may be to blame.

Solid aerosols from the Arctic "didn't look like anything we had ever seen in the literature, in the Arctic, or anywhere else in the world."

Icy clouds could have kept early Mars warm enough to form rivers and lakes, a new study using computer models suggests.

Pristine air over the Southern Ocean suggests clouds from the industrial era weren't so different from those of today, researchers say.

The interaction between bacteria and algae in the world's oceans may play a role in cloud formation, new research indicates.

Ship emissions make the clouds near their routes brighter, researchers say. The clouds can reflect the sun and keep the Earth cooler.