NASA Earth ObservatoryISS program

This 2023 astronaut photo shows a pair of perfectly aligned "wave clouds" rippling above the Crozet Islands in the Southern Ocean. The unusual patterns are the result of changes in temperature caused by gravity waves.

This 2018 astronaut photo shows a striking section of the Green River as it winds through Utah's "Labyrinth Canyon." The canyon's steep walls cast long shadows that hide many secrets, including caves and abandoned uranium mines.