Star trails create arches over the horizon in a long-exposure picture of the night sky taken from Mount Kilimanjaro in Tanzania.
Equatorial regions, such as Kilimanjaro, are the only places on Earth where the celestial poles sit right at the horizon. At night the stars appear to drift overhead from east to west, completing a full circuit around the sky in 24 (sidereal) hours.The image 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.
The bottom image is of the south celestial pole. Not sure about the top one.