On Wednesday afternoon, Central European summer time, will be worldwide and six press conferences of astronomers at the same time. The names of the Parties suggest that there might be big news to a Black hole. Specifically: the first real shots from the edge of such.
by its Nature, a black hole can not be photographed. Due to the enormous gravitational radiation comes out, which could be registered by so-sensitive measuring devices. But the edge of the Black hole, a Zone close to the event horizon, it can theoretically be shown. It marks the boundary between the cosmos and its physical laws as we know it, and the hole itself, where the physics goes crazy.
On our side of the event horizon, matter rotate at nearly the speed of light around the hole is heated to millions of degrees Celsius and sends radiation back into space, which can be from the earth and from space telescopes detected.
Small event horizon
want to look closer to astronomers of the event horizon itself, the more difficult it will be. The reason: He is very small. In the case of a stellar Black hole, i.e., one that has around ten times as much mass as our sun, the event horizon has a diameter of around 60 kilometres. No Chance to see it with a telescope, if the Black hole is a bit further away.
In a real heavyweight like the super massive Black hole in the center of the milky way, has about four million solar masses, the event horizon, although much larger - but still smaller than the orbit of the planet mercury around the sun, has a Radius of about 60 million kilometers.
Because of that supermassive Black hole is located about 26.000 light-years, appears the event horizon as seen from earth is tiny. Like a grain of mustard seed to Times Square in New York, the attempts of Berlin. Even with the best telescope to.
unless, that is, combining several radio telescopes. Then it might be able to make the event horizon of a Black hole is visible – this idea formulated in the year 2000, the astrophysicist Fulvio Melia, Eric Ago, and Heino Falcke, who conducted research at the Max-Planck-Institute for radio astronomy in Bonn (MPIfR) and now a Professor at the Radboud University Nijmegen.
The method is called VLBI (Very Long Baseline Interferometry) and is already a bit older. It is based on radio waves from a distant source which may be a Pulsar or the environment of a Black hole – single radio telescopes on the earth at different times. Depending on which is closer.
on the Basis of the time difference on the one hand, the distances between the telescopes can be determined very precisely. You can on the other hand, take but also the measured signals from different telescopes and in Computer and evaluate it. In this way, a virtual network of several radio telescopes.
The farther they are away from each other, the better the spatial resolution. One has a sufficiently sensitive radio telescopes, and are to be set apart only far enough, so the idea of the researchers, could be the event horizon of a distant Black hole. It took several years to gain the necessary telescopes for the network "Event Horizon Telescope", or technically according to equip.
In April 2017, the astrophysicist eight telescopes in Hawaii, Chile, Mexico, Spain, the USA and the South pole – have aligned for six days, on different targets and the received radio waves, recorded. The spatial resolution of the virtual radio telescope is about a thousand times better than the Hubble space telescope.
Good image, bad image, or no image?
is Particularly intensive, the alleged Black hole in the center of the milky way, called Sagittarius A has been observed, as well as that of the giant galaxy M87. The recorded signals were evaluated on super-computers at the MPIfR in Bonn as well as at the Haystack Observatory Haystack, Massachusetts (USA). The results will now be presented to the Public.
Something Exciting is about to be, or else the consortium would not have recognized six parallel press conferences from Santiago de Chile to Tokyo, as well as various live streams. With great anticipation is expected, whether there is a passable image of a Black hole.More about
astronomy A Reporter from the edge of the holeRalf Nestler
And, above all, whether or not this looks different than theoretical predictions. Because this could be an indication that Einstein's ailing General theory of relativity in the area of extreme physics, the event horizon is. This would be the case, here could be the key to the theory of relativity, is responsible for the macro-cosmos, with the quantum theory, is responsible for the micro-cosmos – together.