Blazar-made intergalactic 'ghost' heralds new era in astronomy

In this artistic composition a distant source emits neutrinos that are detected below the Antarctic ice by Ice Cube Neutrino Observatory sensors called DOMs

Neutrinos, Italian for "little neutral ones", are often described as "ghost particles", for their extremely weak interactions with ordinary matter.

Neutrinos are uncharged subatomic particles that typically go by the trillion through our bodies and all aspects of the Earth each second, however, they once in a while associated with issue - a reality that makes them hard to identify.

The observations were made by the National Science Foundation-supported IceCube Neutrino Observatory at the Amundsen-Scott South Pole Station and confirmed by telescopes around the globe and in Earth's orbit.

Telescopes on the ground and in orbit immediately started scanning the region of space the neutrino came from, searching for anything that might have been energetic enough to launch it.

An artist's impression of a super-massive black hole at the heart of a blazar galaxy shooting a high-energy beam of radiation into space.

Higher energy neutrinos coming from other galaxies are easier to spot than those from our sun, said particle physicist Michelle Dolinski of Drexel University, because faster neutrinos are more likely to smash into things. This blazar, designated TXS 0506+056, is about four billion light years from Earth.

Cosmic rays are charged particles whose paths can not be traced directly back to their sources due to the powerful magnetic fields that fill space and warp their trajectories. This eruption of the blazar could also be detected with other observations - from radio radiation to gamma radiation. 5,160 light sensors were lowered into those holes and spread out over one cubic kilometer. Using that knowledge, an worldwide team of scientists has worked backwards from a neutrino detection to determine where it came from.

"Where exactly in the active galaxy, the neutrinos are produced will be a matter of debate", he added in an email.

However, the source of one high-energy group, known as cosmic neutrinos, has remained particularly elusive. Using software developed by DESY researchers, the gamma-ray satellite Fermi, operated by the USA space agency NASA, had already registered a dramatic increase in the activity of this blazar, whose catalogue number is TXS 0506+056, around 22 September.

Blazars are thought to generate neutrinos and gamma rays, possibly explaining at least one source of cosmic rays. Some of these are called "Oh-My-God particles", because a single particle can smash into the Earth with the force of a 50-plus miles per hour baseball-an object that's more than a trillion trillion times more massive.

Scientists have wondered for a very long time what is the origin of these cosmic rays that attack the Earth, and now they were able to finally come up with an answer. This is farther than any other neutrino whose origin scientists can identify.

Two gamma-ray telescopes, NASA's orbiting Fermi Gamma-ray Space Telescope - which had already observed enhanced gamma-ray activity from the direction of the blazar during its regular scans of the entire sky every three hours - and the Major Atmospheric Gamma Imaging Cherenkov Telescopes (MAGIC) in the Canary Islands, looed in the direction provided by NSF's IceCube.

Following the September 22 detection, the IceCube team quickly scoured the detector's archival data and discovered a flare of more than a dozen astrophysical neutrinos detected in late 2014 and early 2015, coincident with the same blazar, TXS 0506+056. "We're beginning to have more than one sense". On the subatomic scale, the gravity of a neutrino is extremely weak and these particles normally pass through matter completely undetected at almost the speed of light.

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