The Large High Altitude Air Shower Observatory (LHAASO) in Sichuan, China reported a 1.4 PeV photon from the Cygnus region in Nature in 2021, then in February 2024 reported photons up to about 2.5 PeV from a giant gamma-ray bubble in the Cygnus star-forming region — the highest-energy photons ever detected, roughly a quadrillion times the energy of visible light.
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The Large High Altitude Air Shower Observatory (LHAASO) in Sichuan, China reported a 1.4 PeV photon from the Cygnus region in Nature in 2021, then in February 2024 reported photons up to about 2.5 PeV from a giant gamma-ray bubble in the Cygnus star-forming region — the highest-energy photons ever detected, roughly a quadrillion times the energy of visible light.
The highest estimated energy of any individual photon detected from an astrophysical source.
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The frontier as it changed over time.
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1 accepted Claim, with 1 linked evidence records.
Permanent ID limitsregistry.com/limits/LR-HIGHEST-ENERGY-PHOTON
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Limits Registry. LR-HIGHEST-ENERGY-PHOTON. Highest-energy gamma-ray photon detected. 2026.