Scientists Intrigued by "Star Grinder" Pulverizing Entire Star Systems in Our Galaxy
As detailed in a new paper to be published in the journal Astronomy & Astrophysics and first spotted by Universe Today, astronomers in the Czech Republic and Germany suggest that B-type stars, which are only a few times the mass of the Sun, as well as much heavier O-type stars, are being blended up with tens of thousands of smaller black holes near Sagittarius A*, the supermassive black hole at the center of our galaxy.
According to the theory, only the smaller and older B-type stars can survive this ordeal, with the much more massive O-type stars succumbing to their early demise less than five million years into their lifespan — and turning into more small black holes in the maelstrom instead.
The research could force us to reconsider what we know about the violent events happening at the center of our galaxy — a brutal cycle of life and death, right at the core of the Milky Way.
The research could also explain an observation that has puzzled astronomers for years. Within less than a tenth of a light-year from Sagittarius*, O-type stars are nowhere to be found. B-type stars, however, are the predominant type so close to the giant black hole, many of which have been observed to be ejected from the center at extremely fast speeds.
"The smaller B-stars can survive much longer, in fact for some 50 million years," said lead author and Charles University, Czechia, astronomy PhD Jaroslav Haas in a statement. "This explains why the heavy O-type stars are missing at distances smaller than about one-tenth of a light year from SgrA*, with only B-stars surviving there."
"These results give us an entirely new understanding of the immediate surroundings of the central super-massive black hole," explained coauthor and Charles University astrophysicist Pavel Kroupa.
Haas and his colleagues found that the density of black holes actually increases as you move away from the galactic center, before dropping again at a certain distance.
Such a density profile is a "result of the complicated dynamical processes near the central super-massive black hole and our results will allow us to perform new computer simulations to better understand these," explained coauthor and head of the Charles University Astronomical Institute Ladislav Šubr.
The researchers are now excited to better understand the "violent pack of thousands of black holes at the center of our Galaxy that is continuously destroying the stars down there," according to coauthor and Charles University astronomer Myank Singhal.
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