Tag: gamma-ray bursts

The Economist this week reports on the work of Tsvi Piran and Raul Jimenez, calculating the frequency of gamma-ray bursts. This is not an arcane question.
Gamma-ray bursts are incredible yet short-lived generations of energy, cause as yet unknown, great enough to kill all life on a planet as close to the blast as 10,000 light-years (just shy of six quadrillion miles). The closer you get to the center of a galaxy, the more frequent gamma-ray bursts are — and thus, the more inhospitable that region is to life.
Douglas Adams described our home star as being in “the unfashionable end of the western spiral arm of the galaxy.” Turns out, the galactic suburbs may be the only place life could survive long enough to become intelligent.
But wait, there’s more. By Piran and Jimenez’s reckoning, our galaxy is one of the ten percent of galaxies with a high “metallicity” — meaning, with stars full of elements other than hydrogen and helium. In metal-rich galaxies, gamma-ray bursts are rarer. So, not only are we made from the ashes of older stars, but we live in a place with enough star-ash that we are less threatened with gamma-ray extinction.
In short, we might be among the first intelligent life forms.
This is a lovely, trippy idea, made earthier and more bitter by our recent brush with nuclear armageddon. It is also an idea almost completely unexplored in fiction or myth.
(more…)