With neutrinos, scientists observe our galaxy in a whole new way

scientists have detected high-energy neutrinos in pristine ice deep below Antarctica’s surface, then traced their source back to locations in the Milky Way to produce an image of the galaxy made from the subatomic particles

Human beings for millennia have gazed with awe at the vast torrent of stars - bright and dim - shining in Earth's night sky that comprise the Milky Way. Our home galaxy, however, is now being observed for the first time in a brand new way.

Scientists said on Thursday they have produced an image of the Milky Way not based on electromagnetic radiation - light - but on ghostly subatomic particles called neutrinos. They detected high-energy neutrinos in pristine ice deep below Antarctica's surface, then traced their source back to locations in the Milky Way - the first time these particles have been observed arising from our galaxy.

This view differs fundamentally from what we can see with our own eyes or with instruments that measure other electromagnetic sources like radio waves, microwaves, infrared, ultraviolet, X-rays and gamma-rays. It is not stars and planets and other stuff observable thanks to their light, but rather the mysterious sources of neutrinos originating in the galaxy, perhaps remnants of explosive star deaths called supernovas.

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The neutrinos were detected over a span of a decade at the IceCube Neutrino Observatory at a U.S. scientific research station at the South Pole, using more than 5,000 sensors covering an area the size of a small mountain.

"This observation is ground-breaking. It established the galaxy as a neutrino source. Every future work will refer to this observation," said Georgia Tech physicist Ignacio Taboada, spokesperson for the IceCube research.

"When we discovered neutrinos of cosmic origin in 2013, it was somewhat of a surprise to us that we did not find a flux that originated in the nearby sources of our own galaxy. Galactic sources were supposed to dominate the sky, as they do in all wavelengths of light. It took us a decade to discover our own galaxy," said University of Wisconsin physicist and IceCube lead scientist Francis Halzen.