News Astronomy

A rare, extremely energetic cosmic ray has mysterious origins

Efforts to find the particle’s birthplace led scientists to a mostly empty void in space

An illustration of a shower of particles in Earth's atmosphere produced by a cosmic ray. Detectors on the ground spot the particles in the shower.

When cosmic rays hit Earth’s atmosphere, they create a shower of other particles (illustrated) that can be spotted with detectors on the ground (colored dots).

Osaka Metropolitan University/L-INSIGHT, Kyoto University/Ryuunosuke Takeshige

By Emily Conover

The “Oh-My-God” particle has a new companion.

In 1991, physicists spotted a particle from space that crashed into Earth with so much energy that it warranted an “OMG!” With 320 quintillion electron volts, or exaelectron volts, it had the kinetic energy of a baseball zipping along at about 100 kilometers per hour.