Antarctic observatory reveals ‘ghost particles’ in Milky Way for the first time

The Milky Way seen with neutrinos (ICECUBE/NSF)
The Milky Way seen with neutrinos (ICECUBE/NSF)

A never-before-seen view of the galaxy has been glimpsed thanks to an astronomical detector buried in the Antarctic ice.

The blurry image is of the Milky Way - but is composed of the “ghostly” subatomic particles emitted by the reactions that power stars.

Scientists said they produced the image not based on electromagnetic radiation - light - but on particles called neutrinos, which are extremely difficult to detect on Earth.

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.

The data was collected by the IceCube observatory (ICECUBE/NSF)
The data was collected by the IceCube observatory (ICECUBE/NSF)

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.

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.