A Black Hole 'Double Burps'

The galaxy SDSS J1354+1327 (just below the center of the image) hosts a supermassive black hole that has let out two "burps" in the past 100,000 years. The older burp can be seen to the lower left of the galaxy as a diffuse, blue-green glow. The more recent burp appears as a bright blue-white arc to the upper left of the galaxy's center. Its companion galaxy, SDSS J1354+1328, lies just above the center of the image. (Credit: NASA , ESA, and J. Comerford/University of Colorado-Boulder) Supermassive black holes reside at the center of most, if not all, massive (and possibly low-mass) galaxies. They range in size from millions to billions of solar masses, and they can eat voraciously or not at all, depending on their surroundings. But one thing is clear: Black holes don’t have very good table manners, as a team led by researchers at the University of Colorado Boulder confirmed last week at the 231st Meeting of the American Astronomical Society in Washington, D.C. The team caught a supermassive black hole in the galaxy SDSS J1354+1327 (or J1354, for short) with a history of “snacking” on material in its vicinity, then letting out “burps” of energy as a result. In between meals, the black hole is relatively dormant. That dormant period lasted about 100,000 years, which is an eyeblink on cosmological timescales, but certainly not for humans. The work, presented at the Washington, D.C., meeting by Julie Comerford of the University of Colorado and published November 6 in The Astrophysical Journal, identifies two separate burps, or outflow events: one ancient burp on the verge of dissipating and one hinting at a much more recent meal. It is the first time two separate events have been identified for a single galaxy.