Using the Ultraviolet/Optical Telescope aboard NASA’s Neil Gehrels Swift Observatory, astronomers have detected hydroxyl (OH) gas — a chemical fingerprint of water — from the interstellar object 3I/ATLAS. Stacked images of the interstellar comet 3I/ATLAS acquired with the Ultraviolet/Optical Telescope aboard NASA’s Neil Gehrels Swift Observatory: the first were obtained on July 31 and August 1, 2025 (visit 1, top half of figure) and...
