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Anne’s Picture of the Day: Lenticular Galaxy NGC 1277
read more at Anne’s Astronomy News http://annesastronomynews.com/
January 24, 2013
NGC 1277, a galaxy with an extremely massive black hole
Image Credit: NASA / ESA / Andrew C. Fabian / Remco C. E. van den Bosch (Max Planck Institute for Astronomy)
NGC 1277 is a small, flattened lenticular galaxy of roughly 25,000 light-years across, located about 220 million light-years away in the constellation of Perseus, while speeding away from us at approximately 5066 kilometers per second. It is a member of the Perseus Cluster of Galaxies. This galaxy is best known for containing an unusually heavy supermassive black hole.
On November 28, 2012, astronomers reported the discovery of a supermassive black hole in its center what could be the most massive black hole ever found. The black hole is 17 billion times more massive than the Sun, equivalent to 14% of the total stellar mass of the galaxy.
The mass of the current record holder is estimated to lie between 6 and 37 billion solar masses; if the true value lies towards the lower end of that range, NGC 1277 breaks the record. At the least, NGC 1277 harbors the second-biggest known black hole.
As far as we know, almost every galaxy should contain a supermassive black hole in its central region: a black hole with a mass between that of hundreds of thousands and billions of Suns. For instance, the supermassive black hole in our Milky Way galaxy, has a mass of about four million Suns.
Until this discovery astronomers believed that there is a direct relationship between the mass of a galaxy’s black hole and that of the galaxy’s stars. Typically, supermassive black holes do not exceed 0.1% of the mass of their host galaxies. But the supermassive black hole in NGC 1277 could upset the accepted relationship between black hole mass and galaxy mass, which plays a key role in all current theories of galaxy evolution.
In addition, most extremely massive supermassive black holes are found in very large elliptical galaxies. Instead, this black hole sits inside a fairly small disk galaxy.
Is this surprisingly massive black hole a freak accident? Preliminary analysis of additional data suggests otherwise – so far, the search has uncovered five additional galaxies that are comparatively small, yet, going by first estimates, seemed to harbor unusually large black holes too. More definite conclusions have to await detailed images of these galaxies.
If the additional candidates are confirmed, and there are indeed more black holes like this, astronomers will need to rethink fundamentally their models of galaxy evolution. In particular, they will need to look at the early Universe: The galaxy hosting the new black hole appears to have formed more than 8 billion years ago, and does not appear to have changed much since then. Whatever created this giant black hole must have happened a long time ago.
This image is taken with the Hubble Space Telescope.
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2013-01-24 06:15:30
Source: http://annesastronomynews.com/annes-picture-of-the-day-lenticular-galaxy-ngc-1277/
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