The vast majority of galaxies that astronomers observe the sky with their telescopes have at their core a supermassive black hole. A true “space beast” that devours everything around it, but at the same time holds together and in order to hundreds of billions of stars in the galaxy to which they belong. For example, in the center of the Milky Way, our home in space, sleeping Sagittarius A *, a black hole with an area equivalent to four million suns mass. Although this is not, by far the largest of which have been observed so far.
Out there, in the heart of other galaxies have been discovered and true “monsters” with hundreds, even billions of times the mass of the sun. One of the biggest, the center of the NGC 1277 galaxy, 220 million light years from Earth has, for example, 17,000 million solar masses. And much further, to 3,500 million light years away in OJ 287, a binary black hole system reaches an estimated 18,000 million solar masses mass record.
But how far can a black hole grow? A team of researchers from Britain’s University of Leicester has just discovered that, in theory, black holes could grow in galactic centers to 50,000 million solar masses before losing forever the disks of dust and gas around them and They serve as their livelihood.
In a study just published in Monthly Notices of Royal Astronomical Society and teh available arxiv.org, Andrew King, Department of Physics and Astronomy at the University of Leicester study explores both holes supermassive galactic centers as large disks of material , attracted by gravity, they stay around. The gas can form these huge rings lose energy and fall into the black hole, making feeding and bigger, but these drives are also often very unstable and tend to fragment and form new stars.
King has calculated how large could become a black hole before losing its disk of gas. And the result is 50,000 million solar masses. The study suggests that, after losing the disc, the black hole would stop growing, which means that mass, 50,000 million times the Sun, the upper limit would be possible for one of these dark space objects size. The only way to grow above that limit would capture the star hole and pass near the swallow, or to merge with another black hole, joining the mass of both. Although it would be very difficult to observe in such cases.
In the words of King, “the meaning and importance of this discovery is that astronomers observing the enormous amount of radiation produced by gases from disk to fall into black holes have already found huge specimens, with masses close to the limit. The weight limit means that this procedure would not be possible to find black holes much larger than those already known since around their no longer have a luminous disc that allowed us to watch. “
How could we, then, to find even larger black holes? For King, “the existence of even larger black holes is in principle possible. For example, a black hole with a mass close to the limit could join another black hole, resulting in one even greater. But this kind of merger They not produce radiation that we could measure, and the resulting black hole would not around a disk of gas that emit any light. “
However, the researcher does not rule out that we could see one of these “super monster” with an alternative method. “It is possible to detect otherwise. For example, watching how the rays of light from other galaxies are bent when passing by (what is known as gravitational lensing.) Or perhaps, in the future, detecting gravitational waves , predicts the General Theory of Relativity, would occur during the merger of black holes. “
— AVP2
No comments:
Post a Comment