This light is emitted when a gamma ray from a distant source strikes a molecule in Earth’s atmosphere and starts a charged-particle shower. H.E.S.S. is sensitive to some of the highest energy photons (TeV) crossing the universe. Operating since 2003 in Namibia, H.E.S.S. has searched for dark matter and has discovered over 50 sources emitting high energy radiation including supernova remnants and the centers of galaxies that contain supermassive black holes. Pictured last September, H.E.S.S. telescopes swivel and stare in time-lapse sequences shot in front of our Milky Way Galaxy and the Magellanic Clouds — as the occasional Earth-orbiting satellite zips by.
Image & info via APODhttps://apod.nasa.gov/apod/astropix.html
Video source for the gif: https://www.youtube.com/watch?v=iRL268cXaqk
Video Credit & Copyright: Vikas Chander, H.E.S.S. Collaboration;