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Astronomy

The Origin and Distribution of Ultra-High-Energy Cosmic Rays

Quick fact

The most energetic cosmic ray ever detected, the 'Oh-My-God particle' in 1991, carried about 3 × 10^20 electronvolts—an energy level comparable to a well-thrown fastball, yet packed into a single subatomic particle. It likely travelled from beyond our galaxy, as our Milky Way could not plausibly produce such energy.

Why this is interesting

Every second, a particle zooms through the cosmos with the energy of a thrown baseball—yet it's smaller than an atom. Where does such incredible power come from?

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The Origin and Distribution of Ultra-High-Energy Cosmic Rays

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