Scientists think they solved the mystery of the Amaterasu particle
The mysterious Amaterasu particle may not be a proton at all. New research suggests that some of the most extreme cosmic rays could be ultraheavy atomic nuclei, heavier than iron, which are better ab…
The mysterious Amaterasu particle may not be a proton at all. New research suggests that some of the most extreme cosmic rays could be ultraheavy atom
Read Full Story at ScienceDaily →Why This Matters
The discovery could redefine our understanding of cosmic ray origins, challenging the long-held assumption that the most energetic particles are primarily protons. If confirmed, these ultraheavy nuclei would suggest even more violent and exotic astrophysical processes at play in the universe, reshaping theories about cosmic particle acceleration.
Background Context
First detected in 1991 by the Fly's Eye experiment in Utah, the Amaterasu particle—named after the Japanese sun goddess—was a cosmic ray with energies exceeding 200 exa-electronvolts, nearly 100 million times more powerful than the Large Hadron Collider can produce. Its origin has baffled scientists for decades, as no known astrophysical object within our local universe appears capable of producing such extreme particles.
What Happens Next
Next-generation observatories like the Pierre Auger Observatory’s upgrade and the planned Telescope Array Expansion will conduct targeted searches for these ultraheavy cosmic rays, potentially validating the new model. If detected, these particles could serve as probes into distant, unknown cosmic events, offering a new window into the most energetic phenomena in the universe.
Bigger Picture
This finding aligns with growing evidence that extreme cosmic rays may originate from rare, transient events—such as magnetars or colliding galaxies—rather than steady-state sources like supernovae. It also underscores how cosmic ray research continues to push the boundaries of particle physics and astrophysics, bridging gaps between laboratory science and cosmic-scale mysteries.
