Network of Valencian Universities for the Promotion of
Research, Development and Innovation (RUVID) | 2014 Nov 11
An international group of researchers with the participation of the Astronomic Observatory of the Universitat de València has discovered the first lightning bolts from a black hole by eruption with the strongest brightness variations in an extragalactic object ever observed. In an astronomic sense, we are dealing with flashes with duration of only five minutes. The outcomes of the research on this incredibly strong gamma ray phenomenon in the IC 310 galaxy were published in Science.
The IC 310 radio galaxy in the Perseus constellation is 260 million light-years away from the Earth. Astronomers believe its center holds a supermassive black hole. Within this galaxy’s center, a strong gamma ray eruption was produced; it was detected by the telescope MAGIC at La Palma Island, with complementary images from the European VLBI Network (EVN).
Researchers noted with surprise variations in the radiation coming from the IC 310 galaxy on five-minute time scales. “The event horizon of the black hole -- the surface space-time from which nothing can escape the black hole, not even light -- is three times higher than the distance between the Earth and the Sun; that is, 450 millions of kilometers. Light needs 25 minutes to cover that distance,” explained Eduardo Ros, researcher from the Max Planck Institute for Radio Astronomy and the Universitat de València, co-author of the project.
An object cannot completely change the brilliance of its surface in less than the time light needs to pierce it. Hence, the region this gamma ray comes from has to be lower, even more than the event horizon in the black hole, according to the researchers. This implies that astronomers have managed to observe the IC 310 galaxy even in more detail than the size of the central black hole. Additionally, there is to discover what happens in the gravitational trap that the object has created in space. ...
Black hole lightning due to particle acceleration at subhorizon scales - J. Aleksić et al
- Science (online 2014 Nov 06) DOI: 10.1126/science.1256183