Gamma rays may have devastated life on Earth
From New Scientist again: A devastating burst of gamma rays may have caused one of Earth's worst mass extinctions, 443 million years ago.
All the bursts astronomers have recorded so far have come from distant galaxies and been harmless on the ground, but if one occurred within our galaxy and was aimed straight at us, the effects could be devastating, according to astrophysicist Adrian Melott of the University of Kansas in Lawrence.
Very interesting theory! And it should remind us of what is our place in the Universe.