Second OMG cosmic ray particle breaks physics again

Extremely high energy cosmic ray zips through Utah.

A UTAH telescope has spotted the secondlargest cosmic ray ever detected, leaving astronomers stumped.

Cosmic rays are highly energetic streams of subatomic particles that travel at nearly the speed of light. These particle streams are constantly raining down on Earth, and when they collide with atoms in upper atmosphere, they create new particles like positrons, muons, pions and kaons.

In 1991, astronomers detected the highest-energy cosmic ray ever seen. It was dubbed the “Oh-my-god” particle because nothing in the galaxy had the power to produce it and it had more energy than theoretically possible for a cosmic ray travelling from another galaxy: 320 exa-electron volts (320 with 18 zeroes after it). For reference, a single exa-electron volt (EEV) is about a million times larger than the energy generated by the most powerful particle accelerators made by humans.

No cosmic ray came close to the Oh-my-god particle, until one measuring 244 EEV struck the Telescope Array experiment in Utah, US, in May 2021. A paper detailing the discovery was recently published in the journal Science.

“No promising astronomical object matching the direction from which the cosmic ray arrived has been identified, suggesting possibilities of unknown astronomical phenomena and novel physical origins beyond the Standard Model,” says study leader Toshihiro Fujii from Osaka Metropolitan University.