At the moment, the black hole at the heart of the Milky Way is going hungry. But its diet may soon be over: a gas cloud has ventured too close to the super massive black hole and will be devoured by it over the next few years. The feeding of the black hole will be observed by astronomers at first-hand, who should also be able to note a largely increased X-ray emission at the time. Even now they can see how the huge gravitational pull of the black hole is causing some distortion to the gas cloud. The cloud was discovered by an international team of astronomers led by the Max Planck Institute for Extraterrestrial Physics.
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Zoom into the heart of the Milky Way: the black hole is hidden in the part of the sky towards the Saggitarius...
On a clear night, a shimmering band appears to span the skies: the Milky Way. It is part of our galaxy – that system of gas and dust and at least 200 billion stars, of which our sun is also a member. The constellation Saggitarius (from the Latin for the Archer), is particularly rich with stars. Here, hidden behind cosmic clouds, lies the centre of our galaxy. This is where astronomers observe the strong radio source Sagittarius A*. And the scientists suspect that behind it resides a black hole.
At the heart of our Milky Way resides a black hole with about 4.3 million solar masses, as has been proven with long term observations of the motions of stars orbiting this gravitational monster.
At a distance of 26,000 light years, Sagittarius A* is the only super massive black hole close enough to be observed it in detail. Long-term studies of the stellar orbits around this gravitational monster show that it has about 4.3 million solar masses. For most of the time, the black hole lays dormant, emitting modest flares only occasionally. While black holes cannot emit radiation directly by their very nature, the emission from the galactic centre originates from matter falling towards the event horizon, releasing potential energy and heating up.
Analysing very sharp images and detailed observations of the galactic centre with the Very Large Telescope of the European Southern Observatory (ESO), the astronomers have now detected for the first time a gas cloud that is falling into the accretion zone of the black hole. The scientists discovered that the orbit of the cloud is highly eccentric. In the year 2013, it will be closest to the black with a distance of 40 billion kilometres – a very close encounter in astronomical terms.
This will give scientists the ability to watch the spaghetti-fying destruction of the cloud in real time somewhere in the middle of 2013 ..
'We have observed a very unique emission of radio radiation from the centre of our galaxy, the Milky Way.
'By using different methods to separate the signal for very broad range of wavelengths, we have been able to determine the spectrum of the radiation.
'The radiation originates from synchrotron emission - electrons and positrons circulating at high energies around the lines of the Magnetic Field in the centre of the galaxy, and there are quite strong indications that it could come from dark matter.'
Read more: www.dailymail.co.uk... 25sHQYdvp
*Planck satellite picks up beams of radiation from centre of Milky Way which could prove existence of 'dark matter'
*Researchers at Niels Bohr Institute say radiation is either proof - or something currently unknown to physics
By Eddie Wrenn
PUBLISHED: 04:03 EST, 5 September 2012 | UPDATED: 04:03 EST, 5 September 2012
Measurements of stellar orbits1, 2, 3 provide compelling evidence4, 5 that the compact radio source Sagittarius A* at the Galactic Centre is a black hole four million times the mass of the Sun. With the exception of modest X-ray and infrared flares6, 7, Sgr A* is surprisingly faint, suggesting that the accretion rate and radiation efficiency near the event horizon are currently very low3, 8. Here we report the presence of a dense gas cloud approximately three times the mass of Earth that is falling into the accretion zone of Sgr A*. Our observations tightly constrain the cloud’s orbit to be highly eccentric, with an innermost radius of approach of only ~3,100 times the event horizon that will be reached in 2013
I am not really up on or understand what exactly these things are.
Is it true that science does not fully understand what these black holes are?
Is this the only BH in our solar system (milky way)?
Could this be how long distance space travel is accomplished?