Astronomers at the Yale University have discovered an enormous black hole in the early universe which outgrew its galaxy and challenges the theory of galactic evolution.
Until now the observation about black holes suggested that they are massive areas of space with an extremely strong gravity which can pull in anything including light. It was also observed that in most cases, the rate at which the black holes and their host galaxies expand is more or less the same. The recent discovery however proves to be contradictory to all these earlier observations about black holes.
This particular black hole is believed to have been formed roughly two billion years after the Big Bang. An international research group comprising of astronomers from Yale University, ETH Zurich, the Max-Planck Institute in Germany, Harvard University, the University of Hawaii, INAF-Osservatorio Astronomico di Roma, and Oxford University made this discovery when they were mapping the growth of super-massive black holes across cosmic time.
The ancient black hole discovered by the astronomers is comparatively the largest ever found till date. Astronomers believe this black hole is extremely large and more than 7 billion Solar masses (a solar mass is equivalent to the mass of our Sun), another striking feature of this black hole is that the galaxy which surrounds it is only moderately sized, this observation contradicts the theory that larger black holes results into larger galaxies.
This particular black hole is placed at the heart of the galaxy CID-947 and in addition it is so huge that it accounts for about 10% of the total mass of the entire galaxy. The author of the study has claimed in the research paper that it was actually surprising to find a 10% figure and hence the mass of CID-947 was re-measured in a different way, however the result was same. The findings of this study has been published in the July 10 edition of journal Science.
Lead author, Benny Trakhtenbrot, a researcher at ETH Zurich’s Institute for Astronomy says: "The measurements correspond to the mass of a typical galaxy. We therefore have a gigantic black hole within a normal-size galaxy."
Till now researchers have always thought that the size of the galaxy's core and the actual size of the galaxy that surrounds the core has a direct relation in the formation and evolution of galaxies. Further, it is also believed that a lot of heat and radiation gets released during the formation of a black hole and this blocks the formation of stars, thus researchers always thought there is some co-relation between galaxies and their singularities. Presently, researchers believe that most of the galaxies do have black holes at their core.
However, the study of this black hole suggested that not only does the black hole has a very low accretion rate (meaning it is done growing and hence there is low accumulation), but the galaxy surrounding the black hole is still making new stars indicating that the galaxy could further continue to grow.
CID-947 could be a precursor of the most extreme, enormous systems observed in the current local universe, such as the galaxy NGC 1277 in the Perseus constellation that is 220 million light years from the Milky Way. This contradicts the idea that fully formed black holes usually tend to emit too many radio-wave emitting particles which then leads to stop the formation of stars; this is one of the explanation derived by scientists after observing that galaxies which have fully developed black holes at their center tend to cease the formation of new stars.
Researchers used Multi-object Spectrograph for Infrared Exploration (MOSFIRE) camera, that focused into space from the W.M. Keck Observatory atop Mauna Kea, Hawaii, for their findings. MOSFIRE is one of the world's most sensitive near-infrared spectrograph. This brilliant device provided researchers with some in depth details of this galaxy from 11 billion light years away.
C. Megan Urry, Yale’s Israel Munson Professor of Astrophysics and co-author of the study along with her research team have given credit to the W.M. Keck Observatory in Hawaii and the Chandra COSMOS legacy survey which have been of great help in this study. Urry said: "The sensitivity and versatility of Keck’s new infrared spectrometer, MOSFIRE, was critical to this discovery."
Other co-authors of the paper include Francesca Civano, an associate research scientist at Yale; David Rosario, of the Max-Planck Institute; Martin Elvis, of Harvard; Kevin Schawinski, of ETH Zurich and a former Einstein Fellow at Yale; Hyewon Suh, of Harvard; Angela Bongiorno, of INAF-Osservatorio Astronomico di Roma; and Brooke Simmons, of Oxford and a former graduate student at Yale.
It is difficult to test the theory of galactic evolution as it is a very slow process and further quite difficult for astronomers to view the galaxies in their earliest stages because the Universe has existed for a very long time. Researchers ultimately believe that the existing theories are incomplete and they also feel that the fundamental aspects of cosmology might have worked differently towards the early stages of universe.
Urry, said: "Our survey was designed to observe the average objects, not the exotic ones. This project specifically targeted moderate black holes that inhabit typical galaxies today. It was quite a shock to see such a ginormous black hole in such a deep field."
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