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ilan
07-13-2018, 12:56 PM
It Came From a Black Hole, and Landed in Antarctica
Dennis Overbye, New York Times | July 12, 2018

For the first time, astronomers followed cosmic neutrinos into the fire-spitting heart of a supermassive blazar.

https://static01.nyt.com/images/2018/07/13/science/13BLAZAR1/merlin_141145986_b52ed7d7-b5a5-455b-9e25-ba920b39c4e2-superJumbo.jpg
The IceCube Neutrino Observatory in Antarctica, where the tiny particle believed to
have originated in asupermassive black hole was observed last year.

It was the smallest bullet you could possibly imagine, a subatomic particle weighing barely more than a thought. It had been fired out of a gravitational gun barrel by a cosmic blunderbuss, a supermassive black hole.

On Sept. 22, 2017, a particle known as a neutrino zinged down from the sky and through the ice of Antarctica at nearly the speed of light, setting off a cascade of alarms in an array of detectors called IceCube.

Within seconds IceCube had alerted an armada of astronomical satellites, including the Fermi Gamma-ray Space Telescope. That spacecraft traced the neutrino back to an obscure dot in the sky, a distant galaxy known as TXS 0506+056, just off the left shoulder of the constellation Orion, which was having a high-energy outburst of X-rays and gamma-rays.

While astronomers around the world scrambled to their telescopes to get in on the fun, the IceCube scientists scoured their previous data and found that there had been previous outbursts of neutrinos from the galaxy, which they nicknamed the “Texas source,” including an enormous neutrino outburst in 2014 and 2015.

Astronomers said the discovery could provide a long sought clue to one of the enduring mysteries of physics and the cosmos. Where does the rain of high-energy particles from space known as cosmic rays come from?

The leading suspects have long been quasars. They are supermassive black holes in the centers of galaxies where matter and energy get squeezed like toothpaste out of the top and bottom of a doughnut of doomed swirling material in a violent jet.

Now they know at least one in which that seems to be the case. TXS 0506+056 is a type of quasar known as a blazar, in which our line of sight from Earth is along the jet — right down the gun barrel. The term blazar comes partly from BL Lacertae, a starlike object that turned out to be the first of these objects ever recognized.

“We have found the first source of cosmic rays,” said Francis Halzen, of the University of Wisconsin, Madison, and IceCube’s director, in an interview.
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Imagine that -- tracing a subatomic particle back to its supermassive blackhole source millions upon millions of miles away! Putting that in context, I usually have trouble finding my remote in a 12X12 living room. - ilan