The second most energetic cosmic ray discovered in the USA

The Telescopic Array, a cosmic ray observatory in the United States, has detected the second largest cosmic ray, designated by scientists as the “Amaterasu” particle, named after the Japanese sun goddess, the University of Utah reported this Thursday.

The discovery, described in a paper to be published in Friday’s issue of the scientific journal Science, follows the Oct. 15, 1991, discovery of the highest-energy cosmic ray called the “Oh My God” particle. impression that caused among astrophysicists.

The second most energetic cosmic ray was discovered on May 27, 2021, but the results of the experiment became known only now.

According to the North American University of Utah, which along with Japan’s University of Tokyo leads the telescopic array, the energy of this subatomic particle is equivalent to a brick falling from waist height onto your leg.

According to scientists, extremely high energy events such as “Oh My God” and “Amaterasu” particles, although rare and have been detected through various observation methods, are real, but they deepen the mystery of their origin and distribution.

Located in the desert of Millard County, Utah, the telescope array has detected more than 30 extreme-energy cosmic rays since it began collecting data in 2007, but none have come close to the energy of the Oh My God particle, and none no observations were made. revealed their origin or how these energetic particles manage to travel to Earth.

The telescopic array is a collaboration between universities and institutes in the United States, Japan, South Korea, Russia and Belgium and consists of 507 ground detection posts arranged in a square grid covering an area of ​​700 square kilometers (the equivalent of the seven cities of Lisbon).

The infrastructure was designed to observe vast cascades of subatomic particles induced in the Earth’s atmosphere by cosmic rays (which are themselves subatomic particles) with extremely high energy.

The Amaterasu particle activated 23 detectors at the observatory and spread over 48 square kilometers (slightly larger than the city of Porto, which is 41 square kilometers).

According to astrophysicists, who do not specifically know the origin of the second higher-energy cosmic ray, the direction of arrival of this subatomic particle on the Earth’s surface appears to originate from the Local Void, an empty region of space bordering the Earth. The Milky Way, a galaxy that is part of the solar system that includes Earth.

Cosmic rays are charged particles with a wide range of energies, consisting of positive protons, negative electrons or entire atomic nuclei, that travel through space and almost constantly reach the Earth’s upper atmosphere.