Doomed Deep-Space Comet C/2019 Y4 (ATLAS)

This image of comet C/2019 Y4 (ATLAS) was taken on April 20, 2020, showing the comet's solid, icy nucleus breaking apart into as many as 30 pieces that are each roughly the size of a house. The comet was discovered on December 29, 2019 by the ATLAS (Asteroid Terrestrial-impact Last Alert System) robotic astronomical survey system based in Hawaii. ATLAS' fragmentation was confirmed by amateur astronomer Jose de Queiroz, who was able to photograph around three pieces of the comet on April 11. Hubble has a front row seat, with its crisp resolution, to go looking for more pieces. The results are evidence that comet fragmentation is actually fairly common, say researchers. It might even be the dominant mechanism by which the solid, icy nuclei of comets die. Because this happens quickly and unpredictably, astronomers remain largely uncertain about the cause of fragmentation. Hubble's crisp images may yield new clues to the breakup. Hubble distinguishes pieces as small as the size of a house. Before the breakup, the entire nucleus may have been no more than the length of two football fields.