The supermassive black hole at the centre of the Milky Way "eats" asteroids on a regular basis, concluded using the American Chandra X-ray Observatory.
Over the course of several years, Chandra discovered a series of X-ray blasts with a frequency of approximately one a day from the black hole Sagittarius A* (Sgr A*).
Many other powerful instruments like ESO's Very Large Telescope in Chile, the European X-ray satellite XXM-Newton and the Keck telescope in
Hawaii also observed this phenomenon.
The X-ray bursts always last from half an hour to a couple of hours with a brightness that varies from several times to 100 times that of
the black hole's normal 'output'. The disintegration and subsequent vaporisation of asteroids that orbit the black hole may solve the mystery of
the origin of these blasts.
'We think that the blasts from Sgr A* may be caused by the black hole "gorging" itself on asteroids, says Kastytis Zubovas of Leicester University (UK)
and the main author of an article published in Monthly Notices of the Royal Astronomical Society.
The astronomers suggest that a cloud of hundreds of billions of asteroids and comets, pulled from their mother star, surrounds Sgr A*.
Asteroids that pass the black hole at a distance of around 160 million kilometres - roughly the distance from the earth to the sun - are rent into pieces
by the tidal forces of the black hole.
The fragments then vaporise as they fall through the thin hot gas that flows toward Sgr A*, similar to a meteor falling into the earth's atmosphere.
An X-ray flash is produced and what remains of the asteroids is eventually devoured by the black hole.
Although Sgr A* consumes many more smaller asteroids, the authors believe that the blasts are caused by asteroids with a diameter of 20 km or greater.
If the asteroid passes within about 100 million miles of the black hole, roughly the distance between the Earth and the Sun,
it would be torn into pieces by the tidal forces from the black hole. These fragments would then be vaporized by friction as
they pass through the hot, thin gas flowing onto Sgr A*, similar to a meteor heating up and glowing as it falls through Earth's atmosphere.
A flare is produced and eventually the remains of the asteroid are swallowed by the black hole.
(Credit: Illustrations: NASA/CXC/M.Weiss)
The results tally with estimates of the number of asteroids that must be present in the region.
'As a "reality check", we have calculated that the black hole must have devoured several trillion asteroids in the 10 billion years that the Milky Way has
existed,' explains co-author Sera Markoff (UvA). 'Only a fraction of the total number has been swallowed so there is still an ample supply.'
Chandra will continue its observations of Sgr A* in order to collect new information on the frequency and brightness of the blasts and to test the model presented.
Astronomers believe that it will be the same number of powerful blasts in 2012 as in the last 12 years.
Fastest Wind Ever Coming From A Disk Around Stellar-Mass Black Hole Discovered
This record breaking wind is moving about 20 million miles per hour - about 3% the speed of light and may be carrying away much more material
than the black hole is actually capturing.
This is nearly ten times faster than had ever been seen from a stellar-mass black hole, and matches some of the fastest winds g
enerated by supermassive black holes, objects millions or billions of times more massive.
Never Ending Winter In Our Solar System
There's no lack of ice in our solar system.
Frozen water can be found almost everywhere: the poles of Mercury, Earth, the moon and Mars; the rings and icy satellites of the outer planets;
and in comets that come whizzing past.
Winter in our Solar system is not as we know it on our planet.
10 Greatest Astronomical Discoveries
Our Universe is a beautiful and very large place. We have so far only observed a small portion of all marvels our Universe has to offer.
With help of technological breakthroughs, our knowledge will expand and we will soon make new exciting, scientific discoveries.
Here a list of 10 major discoveries that changed how we view the Universe.
Radio Emission From Ultracool Dwarf Detected By Arecibo Telescope
The Arecibo Telescope in Puerto Rico has discovered sporadic bursts of polarized radio emission from the T6.5 brown J1047+21.
Because Arecibo is a single, fixed-dish telescope, it has a restricted practical sensitivity to weak, quiescent emission from radio sources...
Invader From Another Galaxy
This alien intruder from another galaxy is in many ways different from other exoplanets observed by astronomers.
Located about 2000 light-years from Earth in the southern constellation of Fornax (the Furnace), the Jupiter-like planet orbits a dying star of
extragalactic origin and risks to be engulfed by it.
Power To See Most Distant Objects In The Universe
The 3C294, is one of the most distant galaxies recorded by Chandra, the most sophisticated X-ray observatory ever built.
The cluster 3C294 is even 40 percent farther (!) than the next most distant x-ray galaxy cluster.
Chandra focus on X-rays from high-energy regions of the Universe and see the invisible.
It is so sensitive that it can capture images of particles as they disappear into a black hole deep in outer space.