April 6, 2016: Imagine driving through a small town containing modest-sized buildings and seeing a 100-story skyscraper. Astronomers found the equivalent monstrosity in space: a near-record supermassive black hole that weighs 17 billion suns and lives in a cosmic backwater community of a few galaxies. Until now, extremely massive black holes have been found at the cores of very large galaxies in regions of the universe packed with other large galaxies. This is not just coincidence. Like a cosmic Pac-Man, a monster black hole gobbles smaller black holes when two galaxies collide. This game of bumper cars is common in large galaxy clusters. In fact, the current black hole record holder tips the scale at 21 billion suns and resides in the crowded Coma galaxy cluster, located 330 million light-years away.
The newly discovered supersized black hole resides in the center of a massive elliptical galaxy, NGC 1600, located in a small grouping of about 20 galaxies. Astronomers estimate that these smaller galactic groupings are about 50 times more abundant than spectacular galaxy clusters like the Coma cluster. Based on this discovery, astronomers are now asking, Is this the tip of an iceberg? Maybe there are more monster black holes out there that don’t live in a skyscraper in Manhattan, but in a tall building somewhere in the Midwestern plains.
To learn even more about the behemoth black hole in galaxy NGC 1600, join astronomers and scientists during a live Hubble Hangout discussion at 3pm EDT on Thurs., April 7, at http://hbbl.us/z7j.
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March 10, 2016: To learn more about galaxy clusters, including how they grow via collisions, astronomers have used some of the world’s most powerful telescopes, looking at different types of light. They have focused long observations with these telescopes on a half-dozen galaxy clusters. The name for the galaxy cluster project is the “Frontier Fields.” Two of these Frontier Fields galaxy clusters, MACS J0416.1-2403 (abbreviated MACS J0416) in the right panel and MACS J0717.5+3745 (MACS J0717 for short) in the left panel, are featured here in a pair of multiwavelength images.
Located about 4.3 billion light-years from Earth, MACS J0416 is a pair of colliding galaxy clusters that will eventually combine to form an even bigger cluster. MACS J0717, one of the most complex and distorted galaxy clusters known, is the site of a collision between four clusters. It is located about 5.4 billion light-years away from Earth. These new images of MACS J0416 and MACS J0717 contain data from three different telescopes: NASA’s Chandra X-ray Observatory (diffuse emission in blue), Hubble Space Telescope (red, green, and blue), and the National Science Foundation’s Karl G. Jansky Very Large Array (diffuse emission in pink). Where the X-ray and radio emission overlap the image appears purple. Astronomers also used data from the Giant Metrewave Radio Telescope in India in studying the properties of MACS J0416.
For more information about these new images, visit: http://chandra.si.edu/photo/2016/frontier/index.html .
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