Astronomers Spot Giant X-Ray Rings around Stellar-Mass Black Hole
Astronomers using NASA’s Chandra X-ray Observatory and Neil Gehrels Swift Observatory have detected a set of eight X-ray rings around a low-mass black hole in V404 Cygni, a binary system located about 7,800 light-years away in the constellation of Cygnus. These rings are created by light echoes, a phenomenon similar to echoes on Earth from sound waves bouncing off hard surfaces. V404 Cygni is a...