X-ray & Optical Images of Black Hole Pairs
These images show five new pairs of supermassive black holes recently identified by astronomers using a combination of data from Chandra (shown), WISE, and the Large Binocular Telescope. Each pair contains two supermassive black holes weighing millions of times the mass of the Sun. These black hole couples formed when two galaxies collided and merged with each other, forcing their supermassive black holes close together. This discovery could help astronomers better understand how giant black holes grow and how they may produce the strongest gravitational wave signals in the Universe.
(Credit: X-ray: NASA/CXC/Univ. of Victoria/S.Ellison et al. & NASA/CXC/George Mason Univ./S.Satyapal et al.; Optical: SDSS )

Illustration of Dual Supermassive Black Holes
This illustration depicts two centrally located supermassive black holes surrounded by disks of hot gas. The black holes orbit each other for hundreds of millions of years before they merge to form a single supermassive black hole that sends out intense gravitational waves.
(Illustration: NASA/CXC/A.Hobart)