Thursday, May 12, 2011

Sunset Over South America

The Expedition 27 crew photographed this sunset over western South America from aboard the International Space Station. The station crew sees, on average, sixteen sunrises and sunsets during a 24-hour orbital period. Each changeover between day and night on the ground is marked by the terminator, or line separating the sunlit side of Earth from the side in darkness.

While the terminator is conceptualized as a hard boundary and is frequently presented as such in graphics and visualizations, in reality the boundary between light and dark is diffused due to the scattering of light by Earth’s atmosphere.

Image Credit: NASA


See other gifts available on Zazzle.