As the Stars Turn
Star trails create arches over the horizon in a long-exposure picture of the night sky taken from Mount Kilimanjaro in Tanzania.
The shot, captured in July and released this week, shows the apparent motion of the stars around Polaris, the star that's almost exactly aligned with Earth's north celestial pole. Also called the North Star, Polaris is the brightest dot in the constellation Ursa Minor.
Equatorial regions, such as Kilimanjaro, are the only places on Earth where the celestial poles sit right at the horizon.