Gamma Ray Bursts–One Less Thing to Worry About

In case you were worrying that life on Earth would be wiped out by a catastrophic burst of gamma rays, rest easy. It turns out that our galaxy may not be a very good source of gamma ray bursts. I found this particularly interesting given recent speculation that gamma rays bursts might have triggered mass extinctions in the past. (News article here, original paper here.) The bursts are clearly catastrophic, but probably not close enough to Earth to cause much trouble.