Sept. 8, 2022
When photons hurtle toward a black hole, most get sucked into its depths, never to return, or gently deflected away. A rare few, however, skirt the hole, and keep circling the singularity practically forever. Described by astrophysicists as a "cosmic movie camera" and an "infinite light trap," the resulting ring of orbiting photons is among the weirdest phenomena in nature. If you detect the photons, "you're going to see every object in the universe infinitely many times," said Sam Gralla, a physicist at the University of Arizona.