Space

Researchers have detected one of the most powerful cosmic rays ever seen slamming into Earth — but they have no idea what caused it or where it came from. The extremely energetic particle, which has been named after a Japanese goddess, arrived from the direction of a void in the universe where almost nothing is known to exist, according to new research.

Cosmic rays are highly energetic particles, mainly consisting of protons or helium nuclei, that are constantly raining through every square inch of the universe (including our bodies). But a small subsection of cosmic rays, which hit Earth roughly once per square mile every year, are accelerated to even greater energy levels by some of the universe's most intense phenomena.

These extra-energetic particles, known as "ultra-high-energy cosmic rays," have at least one exa-electron volt (EeV), or 1 quintillion (1 followed by 18 zeros) electron volts, of energy, which is around a million times more energetic than the fastest particles from human-made particle accelerators.

On May 21, 2021, researchers detected one of these supercharged cosmic rays with the Telescope Array project — a detector made of individual substations covering more than 270 square miles (700 square kilometers) in Utah. This particular particle had a whopping 244 EeV of energy, which makes it the most energetic cosmic ray since the "Oh My God" (OMG) particle in 1991 — the most powerful cosmic ray ever detected, which had an energy of 320 EeV and traveled at more than 99.9% the speed of light.