This false-color image shows the central region of our Milky Way Galaxy as seen by Chandra. The bright, point-like source at the center of the image was produced by a huge X-ray flare that occurred in the vicinity of the supermassive black hole at the center of our galaxy.
Image: NASA/MIT/F. Baganoff et al.
As black holes go, Sagittarius A* is relatively low-key. The black hole at the center of our galaxy emits very little energy for its size, giving off roughly as much energy as the sun, even though it is 4 million times as massive.
However, astronomers have observed that nearly once a day, the black hole rouses to action, emitting a brief burst of light before settling back down. It’s unclear what causes such flare-ups, and scientists have sought to characterize these periodic bursts in order to better understand how black holes evolve.
For some unknown reason, the black hole at the center of the Milky Way galaxy shoots out an X-ray flare about once a day. These flares last a few hours with the brightness ranging from a few times to nearly one hundred times that of the black hole’s regular output. But back in February 2012, astronomers using the Chandra X-Ray Observatory detected the brightest flare ever observed from the central black hole, also known as Sagittarius A*. The flare, recorded 26,000 light years away, was 150 times brighter than the black hole’s normal luminosity.
What causes these outbursts? Scientists aren’t sure. But Sagittarius A* doesn’t seem to be slowing down, even though as black holes age they should show a decrease in activity.
Mysterious X-ray flares caught by Chandra may be asteroids falling into the Milky Way's giant black hole. Credit: X-ray: NASA/CXC/MIT/F. Baganoff et al.; Illustrations: NASA/CXC/M.Weiss
Earlier this year, a group of researchers said that the outbursts may come from asteroids or even wandering planets that come too close to the black hole and they get consumed. Basically, the black hole is eating asteroids and then belching out X-ray gas.
Astronomers involved in this new observation seem to concur with that line of thinking.
“Suddenly, for whatever reason, Sagittarius A* is eating a lot more,” said Michael Nowak, a research scientist at MIT Kavli and co-author of a new paper in the Astrophysical Journal. “One theory is that every so often, an asteroid gets close to the black hole, the black hole stretches and rips it to pieces, and eats the material and turns it into radiation, so you see these big flares.”
Astronomers detect black holes by the light energy given off as they swallow nearby matter. The centers of newborn galaxies and quasars can appear extremely bright, giving off massive amounts of energy as they devour their surroundings. As black holes age, they tend to slow down, consuming less and appearing fainter in the sky.
“Everyone has this picture of black holes as vacuum sweepers, that they suck up absolutely everything,” says Frederick K. Baganoff, another co-author from MIT. “But in this really low-accretion-rate state, they’re really finicky eaters, and for some reason they actually blow away most of the energy.”
While such events like this big blast appear to be relatively rare, Nowak suspects that flare-ups may occur more frequently than scientists expect. The team has reserved more than a month of time on the Chandra Observatory to study Sagittarius A* in hopes of identifying more flares, and possibly what’s causing them.
“These bright flares give information on the flaring process that isn’t available with the weaker ones, such as how they fluctuate in time during the flare, how the spectrum changes, and how fast they rise and fall,” said Mark Morris from UCLA. “The greatest importance of this bright flare may be that it builds up the statistics on the characteristics of strong flares that can eventually be used to [identify] the cause of such flares.”
Even more intriguing to Baganoff is why the black hole emits so little energy. In 2003, he ran the very first observations with the then-new Chandra Observatory, and calculated that, given the amount of gas in its surroundings, Sagittarius A* should be about a million times brighter than it is — a finding that suggested the black hole throws away most of the matter it would otherwise consume.
The physics underlying such a phenomenon remain a puzzle that Baganoff and others hope to tease out with future observations.
“We’re really studying the great escape, because most of the gas escapes, and that’s not what we expect,” Baganoff says. “So we’re piecing out the history of the activity of the center of our galaxy.”
Paper: Chandra/HETGS Observations of the Brightest Flare seen from Sgr A*
See a movie of the flare here.
Source: MIT
Replies
Rajnish i do not believe that this is a coincidence we are probably looking at a possible stargate, that preciphitates spacial travel making it easier to travel from universe to universe crossing many veils (dimensions) with realitive ease.
plausible, not probable
yes Raj … when we look at the space we see the 'past' of it as it's already happened, so basically we are constantly looking into the past. Sciences learn about the planets, stars, galaxies by their light - visible one with different wavelength … short, long, and etc … and the light years is the faster known to humans way of speed, that's being used right now at this moment, but than again some sciences have found the speed which is faster then "ly' … which it would be difficult to prove … here at this moment …
however the interesting part is 'time' in general …. When we look at the stars/universe - we see the light … now the perception comes in as … the star/universe send the light into the future, we see the light of the star/universe as a past event but we observe it in our present.
It seems that Grand Universe goes through the same transition as we do … Ascension … ;) - as Above so Below.
black holes give off radiation, because of the LAWS of physics energy is never wasted or disappears, only converted. black holes, arent holes at all, and always give off radiation, also not everything is sucked into them, as there are "jets" which shoot off the poles of the black holes. tis is cause by light and other small particles coming in at an oblique angle and bouncing off the black hole and being shot out through its magnetic poles.
good but not good enough … the law of physics applies to physics of physical world, space belongs to something completely different … which often defines the law of ‘human physics, knowledge and perception’ … that’s why there are so many theories … including the one that you presented, which is just a theory.
sigh the reason they are laws is because they apply everywhere. you are in space and thus the laws apply to this planet as much as any other.
or right now in an entangled state.
even more fascinating.
or never in a cynical state.
boring.
Quantum crustacean, the entangled prawn strikes again.
looks good … ;) maybe taste good too?
this happened 26,000 years ago if they are 26,000 light years away.
fascinating.
Thats how the galaxy communicates information to its star children.
So effen obvious.
The Attributes of Conscious Evolution.
I AM apart from the whole.
I AM a part of the whole.
I AM the hole.
I AM that I AM.
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