jueves, 7 de abril de 2016

A SUPERMASSIVE BLACK HOLE WEIGHING 17 BILLION SUNS

Computer simulation of a supermassive black hole at the core of a galaxy
This computer-simulated image shows a supermassive black hole at the core of a galaxy. The black region in the center represents the black hole’s event horizon, where no light can escape the massive object’s gravitational grip. The black hole’s powerful gravity distorts space around it like a funhouse mirror. Light from background stars is stretched and smeared as the stars skim by the black hole.


Astronomers have uncovered a supermassive black hole, weighing 17 billion suns, in an unlikely place in the center of a galaxy in a sparsely populated area of the universe.

The observations made by NASA’s Hubble Space Telescope and the Gemini Telescope in Hawaii, may indicate that these monster objects may be more common than once thought. 

"The newly discovered supersized black hole resides in the center of a massive elliptical galaxy, NGC 1600, located in a cosmic backwater, a small grouping of 20 or so galaxies,” said lead discoverer Chung-Pei Ma, a University of California-Berkeley Astronomer.

Until now, the biggest supermassive black holes those roughly 10 billion times the mass of our sun have been found at the cores of very large galaxies in regions of the universe packed with other large galaxies. 

The current record holder tips the scale at 21 billion suns and resides in the crowded Coma galaxy cluster that consists of over 1,000 galaxies.

The researchers also were surprised to discover that the black hole is 10 times more massive than they had predicted for a galaxy of this mass. 

This black hole is located about 200 million light years from Earth in the direction of the Constellation Eridanus. 

The velocity measurements were made by the Gemini Multi-Object Spectrograph (GMOS) on the Gemini North 8 meter telescope on Mauna Kea in Hawaii. GMOS spectroscopically dissected the light from the galaxy’s center, revealing stars within 3,000 light-years of the core. Some of these stars are circling around the black hole and avoiding close encounters. However, stars moving on a straighter path away from the core suggest that they had ventured closer to the center and had been slung away, most likely by the twin black holes. 

Archival Hubble images, taken by the Near Infrared Camera and Multi-Object Spectrometer (NICMOS), supports the idea of twin black holes pushing stars away. The NICMOS images revealed that the galaxy’s core was unusually faint, indicating a lack of stars close to the galactic center. 

A star depleted core distinguishes massive galaxies from standard elliptical galaxies, which are much brighter in their centers. 

The Astronomers estimated that the amount of stars tossed out of the central region equals 40 billion suns, comparable to ejecting the entire disk of our Milky Way galaxy.