Wednesday 14 August 2013
The black hole at the center of our galaxy has a huge magnetic field. A cosmic beacon helped in its discovery.
addition to the giant black hole at the heart of our Milky Way a cosmic flashing beacon. This has been discovered by Ralph Eatough from the Max Planck Institute for Radio Astronomy in Bonn with the 100-meter radio telescope in Effelsberg in the Eifel astronomers. After such a so-called pulsar in the Galactic Center researchers have sought for two decades. Because the beacon allows new investigations of the central region of our galaxy, as the scientists report in the British journal “Nature”. To the central black hole winds therefore a strong magnetic field.
Pulsars are rapidly rotating neutron stars – are the compact remnants of burned suns. Send as a Lighthouse from a sharply focused beam of light. Stroking on this beam of light the earth, this cosmic flashing beacon on a very regular basis. Astronomers have found a number of pulsars in the universe, just search on the center of our Milky Way had been unsuccessful. The black hole there Swallowing large amounts of gas, and has been incorporated as a mass of four million suns. How the process works in detail, is not fully understood. Magnetic fields likely play an important role. The boundary of the black hole is very difficult to observe and behind the hot gas that accumulates in a swirling disc.
magnetic field around 150 light years away from the black hole
The newly discovered pulsar pulses of light through the outskirts of the gas disk with radio waves. This allows an examination of the magnetic field in the disk. Because the radio pulses are strongly polarized, that is, all the radio waves vibrate in one plane. When passing through a magnetic field, this oscillation plane is rotated, and the more so the stronger the magnetic field. In the peripheral regions of the giant disk of dust about 150 light-years away from the black hole, the researchers in this way establishes a magnetic field whose strength corresponds to theoretical predictions well. It is also relatively uniform and less turbulent than you might expect it in the swirling gas.More about
closer the gas in the disc is the black hole, the stronger the magnetic field. The projected magnetic field strength in the inner disk can explain the observed X-ray and radio emission from the outskirts of the black hole good as the researchers explain. The magnetic field also affects the motion of matter at the transition into the black hole. So it could eject a portion of the hot gas in closely bunched beam vertically up and down from the disc again before it can fall into the black hole. In addition, a strong magnetic field the whole process falls through the matter into the black hole, brake. That might help explain why the black hole in the center of the Milky Way hungry -. Compared to its siblings in other galaxies swallow far more matter
“It’s amazing how much information we can pull an object out of this,” said Adam Deller from the Netherlands Institute for Radio Astronomy, which was involved in the investigation, in a statement. “This discovery is a major breakthrough, but it remains a mystery why it took so long to find a pulsar there,” said Deller’s colleague Heino Falcke. The astronomers hope to detect more beacon in the center of the Milky Way. “If there is a young pulsar there, there should be a lot older – we just have to see,” said Michael Kramer, director said at the Max Planck Institute for Radio Astronomy
Source: n-tv.de‘); display