Some supermassive black holes announce their presence with screaming hot disks of orbiting gases. But the behemoth at the center of the Milky Way has been shy and demure. Now, astronomers have finally spotted the black hole’s faintly glowing accretion disk of infalling material, long suspected but never before seen.
“I was very surprised that we actually saw it,” says astrophysicist Elena Murchikova at the Institute for Advanced Study in Princeton, N.J. The disk was observed using the Atacama Large Millimeter/submillimeter Array, or ALMA, in northern Chile, the researchers report in the June 6 Nature.