Space

Center of Milky Way found to be brimming with black holes

Center of Milky Way found to b...
Scientists have uncovered the first direct proof of black holes surrounding the supermassive black hole at the heart of the Milky Way
Scientists have uncovered the first direct proof of black holes surrounding the supermassive black hole at the heart of the Milky Way
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Scientists have uncovered the first direct proof of black holes surrounding the supermassive black hole at the heart of the Milky Way
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Scientists have uncovered the first direct proof of black holes surrounding the supermassive black hole at the heart of the Milky Way
Scientists have uncovered the first direct proof of black holes surrounding the supermassive black hole at the heart of the Milky Way
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Scientists have uncovered the first direct proof of black holes surrounding the supermassive black hole at the heart of the Milky Way

Scientists have long searched for proof of the decades-old theory that black holes surround the supermassive black hole known as Sagittarius A* that lies at the heart of our galaxy. By tweaking their approach just a little, astronomers have now turned up the first direct evidence that they do in fact exist, creating new opportunities to study the interplay between regular black holes and their much bigger brethren.

Sometimes when a black hole is sucked into and held in the vicinity of a supermassive black hole, they will latch onto a nearby star to form a stellar binary. This mating generates a big burst of X-ray light, which has provided black hole-hunters with a target to search for.

"It's an obvious way to want to look for black holes," explains Chuck Hailey, an astrophysicist at Columbia University and lead author on the new study. "But the Galactic Center is so far away from Earth that those bursts are only strong and bright enough to see about once every 100 to 1,000 years."

Hailey and his team found success by instead searching for the fainter but more consistent X-ray light beamed from the stellar binary after they've bonded, and are resting in an inactive state. They applied this technique to archival data gathered by NASA's Chandra X-ray Observatory, looking out for X-ray signatures of black hole-low mass binaries. They found 12 within three light years of Sagittarius A* that fit the bill nicely.

Scientists have uncovered the first direct proof of black holes surrounding the supermassive black hole at the heart of the Milky Way
Scientists have uncovered the first direct proof of black holes surrounding the supermassive black hole at the heart of the Milky Way

"It would be so easy if black hole binaries routinely gave off big bursts like neutron star binaries do, but they don't, so we had to come up with another way to look for them," Hailey said. "Isolated, unmated black holes are just black – they don't do anything. So looking for isolated black holes is not a smart way to find them either. But when black holes mate with a low mass star, the marriage emits X-ray bursts that are weaker, but consistent and detectable. If we could find black holes that are coupled with low mass stars and we know what fraction of black holes will mate with low mass stars, we could scientifically infer the population of isolated black holes out there."

By extrapolating their results in this way, making use of analysis and spatial distribution of already identified binary systems, they team figures there are between 300 and 500 black hole-low mass binaries in the same region, along with around 10,000 isolated black holes.

"Everything you'd ever want to learn about the way big black holes interact with little black holes, you can learn by studying this distribution," says Hailey. "The Milky Way is really the only galaxy we have where we can study how supermassive black holes interact with little ones because we simply can't see their interactions in other galaxies. In a sense, this is the only laboratory we have to study this phenomenon."

The research was published in the journal Nature.

Source: Columbia University

5 comments
Chris Coles
The outer event horizon, above the outer surface of the mass of a significant size black hole will, inevitably, (due to gravity reducing in force as the point of observation rises from that surface), be a very considerable distance from the surface; might even be a light year or more. The outer event horizon represents the lowest force required to exceed the escape velocity of the photon. Always remembering that, as such, there will not be ANY errant photons of energy between that outer event horizon and the surface of the mass. In which case, it will be possible for a star with mass and momentum, to carry sufficient energy to orbit through the outer event horizon; passing beneath the surface only to come out again at another point on its continuing orbit of the black hole. The event horizon is simply a mathematical calculation. The event horizon has no structure; it cannot impede a mass with momentum from orbiting into and again out of that mathematical point of calculation. There is only a single black hole at the centre of the Milky Way; which has an outer event horizon perhaps more than a light year above, perhaps many light years above; the surface of the mass of the black hole. We are observing stars orbiting within a mathematical calculation described as an event horizon; and out again beyond that calculation.
Bob
There is a big difference between some evidence and direct proof. Extrapolating data is a useful tool if you are looking for a value between two close and accurately known data points. Extrapolating above or below known points becomes very questionable. Extrapolating with assumed values and ratios becomes just another wild guess. When someone uses the words "obvious, sometimes,everything" and give estimates on data that has only been collected for a short time and saying that some data only occurs once in 100 to 1000 years, don't be dazzled by the math. They are just propping up a theory they already believe and making a model to fit. One pixel doesn't make a picture.
KungfuSteve
Most likely, the Center of the Galaxy will be (or soon to become) a Massive Black Hole... and that the Energy Collected from a Blackhole... ends up forming and fueling a Sun, someplace else in a different location in space, or to another plane of reality / dimension / multi-verse...etc. A Blackhole may be a form of Wormhole... and maybe it could actually be usable, before it reaches a certain state of power / development. Everything is nature and the universe, seems to be Cyclical / Balanced. All of that collected energy has to go somewhere, and there seems to be only one thing that shows such massive amounts of energy... as a Sun/Star. The only thing left to clear up, would be a means to determine how / where new physical materials get expelled. Maybe, once the Blackhole has completely run dry... the resulting Star runs out of the needed energy to maintain fusion, and eventually blows physical materials across the galaxy... possibly back out of the failed black hole? or out of the sun side. Maybe even blasting material into an alternate universe / plane / quantum state (forming all over the place in smaller amounts) All of this is merely fractal-patterned + logic based theory, from a self-admittedly, semi-ignorant, source.
Expanded Viewpoint
You are right, Bob. It's like someone is taking a single molecule from a piece of leather, and then building upon that in all directions via extrapolations, interpretations, interpolations and whatnot, and either winding up with a car with a fine leather interior or a whole cow! How did they get from Point A to Point B? They can't really tell you that because they don't know, they just did it by guess and by gosh. "This sounds good, so we'll just run with it." Randy
Douglas Bennett Rogers
A black hole is actually an antimatter engine. Material falling into it emits half of its rest mass in energy. An object orbiting within the Schwarzschild radius doesn't retain enough energy to escape.