Space.com
Cosmic rays pour down on Earth like a constant rain. We don’t much notice these high-energy particles, but they may have played a role in the evolution of life on our planet.
Some of the mass extinctionsidentified in the fossil record can be linked to an asteroid impact or increased volcanism, but many of the causes of those ancient die-offs are still open for debate.
“There may have been nearby astronomical goings-on that drastically increased the radiation on Earth,” says Brian Fields from the University of Illinois.
