NASA's Neil Gehrels Swift Observatory imaged rings of X-ray light centered on V404 Cygni, a binary system containing an erupting black hole (dot at center), with its X-ray Telescope from June 30 to July 4, 2015. The dark lines running diagonally through the image are artifacts of the imaging system.

X-ray Echoes Create Black Hole Bull’s-eye

NASA's Neil Gehrels Swift Observatory imaged rings of X-ray light centered on V404 Cygni, a binary system containing an erupting black hole (dot at center), with its X-ray Telescope from June 30 to July 4, 2015. The dark lines running diagonally through the image are artifacts of the imaging system.

Credits: Andrew Beardmore (Univ. of Leicester) and NASA/Swift