A mysterious, ghostly particle that slammed into Earth and lit up sensors buried deep beneath the south pole has been traced back to a distant galaxy that harbours an enormous spinning black hole.
Astronomers detected the high-energy neutrino, a kind of subatomic particle, when it tore into the southern Indian Ocean near the coast of Antarctica and carried on until it struck an atomic nucleus in the Antarctic ice, sending more particles flying.
The event, which took place on 22 September 2017, was captured by the IceCube experiment, a cubic kilometre of clear ice kitted out with sensors to detect such intergalactic incidents. Within a second of the particle being spotted, IceCube issued an automatic alert, prompting an international race to find the neutrino’s origin.
Because scientists on the IceCube experiment had worked out the path the particle took through their subterranean ice instrument, astronomers knew where in the sky to look for the particle’s source. A string of early observations came up blank, but days later Nasa’s Fermi Gamma-ray Space Telescope spotted the likely source: a flaring “blazar”.
Most galaxies are thought to have spinning supermassive black holes at their centres. But some of these black holes appear to pull in material at ferocious rates, a process that simultaneously sends streams of highly energetic particles out into space. Such galaxies are called blazars, although the term only applies when one of these streams is directed straight at Earth.
For more read the full of article at The Guardian
