Ghostly particle caught in polar ice ushers in new way to look at the universe
By Daniel CleryJul. 12, 2018 , 11:00 AM
If astronomers are right, a ghostly particle that lit up an instrumented swath of ice beneath the South Pole on 22 September last year was a messenger from a distant galaxy. The particle was a neutrino, electrically neutral and almost massless, which means its path could be traced back to the extragalactic event that created it. Cued by IceCube, the Antarctic detector, the orbiting Fermi Gammaray Space Telescope found that the neutrino likely came from a far off blazar, a hugely bright source of radiation powered by a supermassive black hole.
Astronomers have long been tantalized by the prospect of using neutrinos, which move at almost the speed of light and rarely interact with other matter, to learn about violent cosmic events. The new finding, reported today in Science, could mark the founding event of neutrino astronomy. The detection also triggered a powerful example of another new trend, multimessenger astronomy, in which telescopes and other instruments studied the flaring blazar in all parts of the electromagnetic spectrum, from gamma rays to radio waves.
http://www.sciencemag.org/news/2018/07/ghostly-particle-caught-polar-ice-ushers-new-way-look-universe
