Orbital sunrise

An orbital sunrise is the natural light display seen by an observer in low orbit as their spacecraft crosses from Earth's night side to its day side, an event that recurs roughly every ninety minutes for crew aboard the International Space Station. The display begins as a thin blue arc along the horizon that quickly brightens into vivid orange and red, an effect of Rayleigh scattering of sunlight through the atmosphere, and can also reveal polar mesospheric clouds. Cosmonauts Alexei Leonov and Pavel Belyayev, on the Voskhod 2 mission, were the first people to see it; Leonov afterward made colored-pencil sketches of it, considered the first artwork made in space. This description is adapted from Wikipedia contributors under CC BY-SA 4.0; changes were made. https://creativecommons.org/licenses/by-sa/4.0/