Researchers at the University of Utah and the University of Tokyo have made a groundbreaking discovery in the field of astrophysics, detecting the second-highest extreme-energy cosmic ray to date. The cosmic ray, named the “Amaterasu particle,” was observed by the Telescope Array experiment and has left scientists puzzled due to its incredibly high energy levels. This phenomenon challenges current understanding of particle physics and has raised questions about the origin and nature of these ultra-high-energy events.

The history of cosmic ray observation dates back to 1991, when the University of Utah Fly’s Eye experiment first detected the highest-energy cosmic ray ever observed, later named the Oh-My-God particle. This cosmic ray exhibited unprecedented levels of energy, exceeding the theoretical limits for such particles. Despite subsequent observations of more than 30 ultra-high-energy cosmic rays, their origins and ability to travel to Earth remain a mystery to astrophysicists.

The groundbreaking discovery of the Amaterasu particle on May 27, 2021, raises significant questions about the nature of these ultra-high-energy cosmic events. With an energy level of 2.4 x 1020eV, equivalent to dropping a brick from waist height, this single particle indicates the presence of powerful cosmic phenomena. Its arrival direction from the Local Void, an area of empty space bordering the Milky Way galaxy, further adds to the mystery.

In a study published in the journal Science, an international collaboration of researchers describes the rare phenomena of ultra-high-energy cosmic rays and presents the Amaterasu particle as a unique and previously unknown cosmic event. The researchers named the particle after the sun goddess in Japanese mythology, symbolizing the extraordinary nature of the discovery.

The implications of these discoveries extend beyond the realm of astrophysics, with potential implications for the understanding of cosmic phenomena and particle physics. The expansion of the Telescope Array experiment is poised to provide additional insights into these ultra-high-energy events, as researchers continue to unravel the mysteries of the universe.