Scientists have pinpointed the precise locations of a pair of supermassive black holes at the centers of two colliding galaxies 300 million light-years away.
Infrared images made by the Keck II telescope in Hawaii reveal the two black holes at the center of the galaxy merger known as NGC 6240 are each surrounded by a rotating disk of stars and cloudy stellar nurseries.
The new images are detailed in Science Express, an online publication of the journal Science.
Scientists had previously observed NGC 6240 in a piecemeal fashion, using different wavelengths of light. Images captured by the Hubble Space Telescope showed the outer parts of the colliding galaxies in visible light, and revealed long tidal tails made of orphaned stars, gas, and dust.
Subsequent X-ray observations by NASA’s Chandra X-ray Observatory revealed the presence of two supermassive black holes at the center of each galaxy, and the Very Long Baseline Array spotted two radio sources in the galaxies’ central regions. The problem was combining all of the images to form a single coherent picture.
“You have all these different telescopes and they look at the same piece of sky but see wildly different things,” said study team member Willem de Vries of the University of California, Davis.