Ultra-High-Energy Particle Detected in Utah Originating Beyond Our Galaxy
In a groundbreaking discovery, space scientists at the Telescope Array in Utah have identified an extremely rare, ultra-high-energy cosmic ray believed to have journeyed to Earth from outside the Milky Way galaxy. This discovery, detailed in a new study published in the journal Science, sheds light on the perplexing origins of powerful cosmic rays that constantly bombard our planet.
Cosmic rays, composed of charged particles, continuously travel through space, with lower-energy ones originating from the sun. However, the newfound particle, dubbed the Amaterasu particle after the Japanese sun goddess, possesses energy levels equivalent to dropping a brick on your toe from waist height. Its energy matches that of the infamous “Oh-My-God” particle detected in 1991, marking it as one of the most energetic cosmic rays ever observed.
Despite decades of research, the precise source of these ultra-high-energy particles remains elusive. While they are thought to be associated with the universe’s most energetic phenomena, such as black holes and gamma-ray bursts, the exact origins of the detected particles, especially the larger ones, remain a scientific puzzle.
The Amaterasu particle was identified by the Telescope Array, a cosmic ray observatory in Utah’s West Desert. This observatory, operational since 2008, consists of 507 surface detectors covering an expansive area of 700 square kilometers. The recent discovery adds to the more than 30 ultra-high-energy cosmic rays observed by the Telescope Array, with the Amaterasu particle standing out as the most significant.
The event occurred on May 27, 2021, when the particle struck the Earth’s atmosphere above Utah, initiating a cascade of secondary particles that were subsequently captured by the observatory’s detectors. The analysis revealed an energy level of approximately 244 exa-electron volts, making it an unprecedented find, though slightly less energetic than the “Oh-My-God” particle.
Researchers have long theorized that ultra-high-energy cosmic rays may be linked to celestial events like those involving black holes, gamma-ray bursts, or active galactic nuclei. However, the Amaterasu particle, like its predecessors, seems to defy easy categorization. The perplexing aspect is that the trajectories of the two most significant cosmic rays, including the recent discovery, do not seem to point toward any high-energy sources. This adds an additional layer of mystery to the study of these elusive particles.
The Telescope Array Collaboration, led by co-spokesman John Matthews, expressed plans to expand the observatory, adding 500 new detectors. Once completed, this expansion will cover an area of 2,900 square kilometers, allowing for a more extensive examination of cosmic ray-induced particle showers. The hope is that this expansion will provide further insights into the origins and characteristics of these ultra-high-energy cosmic rays, offering a clearer understanding of the mysterious cosmic phenomena.
The atmosphere largely shields Earth from the potential harm of these cosmic rays, with the primary impact being occasional computer glitches. However, the broader implications of such cosmic phenomena and space radiation pose significant challenges for space missions and astronaut safety, emphasizing the need for continued exploration and understanding of these celestial mysteries.