Ice Cube – Astrophysics In July

by Pat Browne

Detection of Cosmic Ray Source Galaxy – a chilling discovery

On July 12 2018, the Ice Cube neutrino Laboratory at the Amundsen–Scott South Pole Station announced the results from last September’s (2017) cosmic neutrino detection; the results confirmed the precise source location and type of galaxy (a Blazar galaxy) that emitted the highly energetic particles. These high energy subatomic particles travelled unhindered for billions of light years from a most extreme galaxy source to Earth – and with luck interacted with detectors in the shielded and deep chill of the South Pole ice . The Ice Cube detector is actually a “Telescope in Ice” – see The Telescope in Ice

Image: Felipe pedreros, icecube/NSF

How The Telescope in Ice captures cosmic Neutrinos:

When a neutrino interacts with the surrounding material, it generates another particle, a muon. The muon rushes on in the general direction in which the neutrino had been going, creating pale-blue radiation – see Cherenkov Radiation . By capturing and analyzing the tracks of blue light along these  arrays of optical modules on strings,  sunk into the ice sheet, a direction to the source in the sky (and the cosmos) can be traced. See also Flavor of Astrophysical Neutrinos in IceCube

What’s so exciting about intergalactic cosmic rays?

Neil De Grasse Tyson describes what’s going on in intergalactic space, quipping “Yes, intergalactic space, is and will be forever, where the action is”…. In the chapter Between the Galaxies from the book Astrophysics for People in A Hurry, Neil explains the nature of cosmic rays coming from charged protons:

courtesy Astrophysics for People in A Hurry, Ch. 4 by Neil De Grasse Tyson

What’s even more exciting about the Ice Cube (multi)Telescope Detection?

The exciting news is that with the help of many other telescopes around the world, astronomers were able to confirm the precise location of the Blazer galaxy that emitted these highly charged particles: With a “little help from our friends”… astronomers pointed their scopes, both ground-based and in orbit,and confirmed that there was a  Blazar source 3 billion light years away: Blazar  TXS 0506+056 – … located in the direction of the constellation of Orion!

“Equipped with a nearly real-time alert system—triggered when a very high-energy neutrino collides with an atomic nucleus in the Antarctic ice in or near the Ice Cube detector—the observatory broadcast coordinates of the Sept. 22 neutrino alert to telescopes worldwide for follow-up observations. Gamma-ray observatories, including NASA’s orbiting Fermi Gamma-ray Space Telescope and the Major Atmospheric Gamma Imaging Cherenkov Telescope, or MAGIC, in the Canary Islands, detected a flare of high-energy gamma rays associated with TXS 0506+056, a convergence of observations that convincingly implicated the blazar as the most likely source.” text and images courtesy Ice Cube neutrinos point to cosmic ray accelerator

Blazar – What in Blazes …

A blazar is a giant elliptical galaxy with a massive, rapidly spinning black hole at its core. A signature feature of blazars is that twin jets of light and elementary particles, one of which is pointing to Earth, are emitted from the poles along the axis of the black hole’s rotation. This blazar is situated in the night sky just off the left shoulder of the constellation Orion and is about 4 billion light years from Earth.

Note that Orion is a winter constellation in the northern hemisphere. Currently our Sun is located in that section of the sky and therefore the constellation is hidden behind the glare of the daytime Sun. When the deep chill is on again in late fall and winter, we can observe that part of the Celestial Sphere… and only imagine what the blazes might be going on 4 billion light years above the left shoulder of Orion – in the direction  of Betelgeuse, the friendly Red Giant. See