Kimiyo Tazu Hoshi, a brilliant but overly-driven scientist, was the supervising astronomer at an observatory in Japan during Crisis on Infinite Earths. The Monitor gives her light-based powers to help battle the Anti-Monitor. Doctor Light has joined the Justice League a few times over the years, most notably as a member of Justice League Europe during the latter half of its incarnation. She also joins the Doom Patrol for a time and enters a relationship with Global Guardians member Rising Sun.