Mysterious cosmic rays from beyond the Milky Way have scientists baffled

[New Sancai Compilation and First Release] Space scientists have discovered an extremely rare ultra-high-energy particle, which is believed to have traveled from outside the Milky Way.

According to CNN, research published in the journal Science on November 23 shows that the energy of this particle is similar to the impact of a brick thrown from waist height to your toe. It is comparable to the famous "Oh-my-god" particle detected in 1991.

Cosmic rays are charged particles that are constantly radiating to the Earth from space and are the focus of scientific inquiry. Low-energy rays come from the sun, and the highest-energy rays are thought to come from distant galaxies and extragalactic sources.

"If you hold out your hand, there's going to be a bunch of [cosmic rays] going through your palm every second, but these are really low-energy things." John Ma, co-author of the study and a research professor at the University of Utah, USA John Matthews explained. "When you're exposed to these really high-energy [cosmic rays], it's more like one per square kilometer per century. So it's never going to go through your hand."

The latest particle, detected by the Cosmic Ray Observatory telescope array in Utah's western desert, has been named the "Amaterasu particle" after the Japanese sun goddess. The observatory has been operating since 2008 and consists of 507 surface detectors covering an area of 270 square miles.

The Amaterasu particles observed on May 27, 2021 triggered 23 surface detectors, and their energy was about 244 exa electron volts; the "Amaterasu" particle detected in 1991 had a voltage of 320 exa electron volts.

According to NASA, 1 exa electron volt is equivalent to 1 billion giga electron volts, and the energy of an Amaterasu particle is 244,000,000,000,000,000,000 electron volts. These ultra-high-energy cosmic rays are tens of millions of times more energetic than any man-made particle accelerator, including the Large Hadron Collider in Geneva, Switzerland.

NASA reports that the typical energy of electrons in Earth's aurora reaches 40,000 electron volts.

While cosmic rays generally pose little threat to humans due to the protective atmosphere, they can cause computer glitches. However, NASA says astronauts face greater risks because space radiation, including cosmic rays, can cause structural damage to DNA and alter cellular processes.

The origin of these ultra-high-energy particles remains a mystery to scientists. Amaterasu particles appear to originate in the Local Void, a region of empty space bordering the Milky Way.

“If you look at the two highest-energy events — that Amaterasu particle we just discovered and the previous OMG particle — they don’t even seem to be pointing at anything. It should be something relatively nearby. It has Astronomers with visible telescopes can't see anything truly huge and this dramatic," Matthews said.

The question remains: What is the nature of these cosmic phenomena that appear to arise from regions devoid of visible violent events?

Expansion of the telescope array is underway to shed light on this cosmic mystery.

When completed, the 500 new detectors will allow the observatory to capture cosmic ray-induced particle showers across approximately 1,120 square miles, providing potential breakthroughs in understanding these mysterious celestial phenomena, according to a statement from the University of Utah.

(Compiled by: Wang Jimin)

(Editor: Jiang Qiming)

(Source of the article: First published by Xinsancai)