‘ Ghost particles help us understand space’

‘ Window to see the cosmos’

Washington: A breakthrough in the study of ghostly particles called high- energy neutrinos that traverse space, zipping unimpeded through people, planets and whole galaxies, is giving scientists an audacious new way to expand our understanding of the cosmos.

Researchers on Thursday said they have for the first time located a deep- space source for these ubiquitous subatomic particles.

They detected highenergy neutrinos in pristine ice deep below Antarctica’s surface, then traced their source back to a giant elliptical galaxy with a massive, rapidly spinning black hole at its core, called a blazar, located 3.7 billion light years from Earth in the Orion constellation.

The key observations were made at the IceCube Neutrino Observatory at a US scientific research station at the South Pole and then confirmed by land- based and orbiting telescopes. Astronomers long have relied upon electromagnetic observations — studying light — but this approach has limitations because too many aspects of the universe are indecipherable using light alone.

The ability to use particles like high- energy neutrinos in astronomy enables a more robust examination, much as the confirmation of ripples in the fabric of spacetime called gravitational waves, announced in 2016, opened another new frontier in astronomy. This emerging field is dubbed “multi- messenger astrophysics.”

“Neutrinos provide us with a new window with which to view the universe,” said University of Alberta physicist Darren Grant, spokesman for the IceCube scientific collaboration. It appears they arise from some of the universe’s most violent locales.