C. D. Fassnacht

Using a network of radio telescopes, astronomers spotted a tiny flaw in a thin arc of a distant galaxy. It revealed an invisible object with a mass of about a million Suns — a hundred times lighter than anything previously weighed at such distances. The discovery proves that gravitational lensing ca

The cosmic lens effect offered a peek inside an invisible object with the mass of a million Suns. Its structure contradicts established theory: the density is uniform throughout, and a black hole likely hides at the center. Perhaps dark matter particles can collide.