02/20/2005: And we squeak out again....
As if the Sumatran tsunami wasn't enough of a reminder how dangerous a place the universe can be, it appears that just the next day (December 27th) astronomers observed one of the biggest stellar explosions ever observed--probably the biggest within our galaxy since Johannes Kepler observed the famous supernova of 1604. The explosion took place on a super-magnetic neutron star (or "magnetar") called SGR 1806-20, which is located in our own galaxy on a different spiral arm, approximately 50,000 light years away.
Still, as far away as it was, the explosion "lit up" the sky here--at least it would have if your eyes were better attuned to gamma-rays rather than visible light. But the release of energy in the explosion--estimated to measure approximately 10,000 trillion trillion trillion watts--caused radiation to bounce off the moon and lit up Earth's atmosphere for a while. Not to mention the effects it could have on any nearby systems which have life on them (if any exist):
SGR 1806-20 is sited in the southern constellation Sagittarius. Its distance puts it beyond the centre of the Milky Way and a safe distance from Earth.However, our friends at the comic strip "User Friendly" have figured it all out.
"Had this happened within 10 light-years of us, it would have severely damaged our atmosphere and would possibly have triggered a mass extinction," said Dr Bryan Gaensler, of the Harvard-Smithsonian Center for Astrophysics, who is the lead author on one of the forthcoming Nature papers.
"Fortunately there are no magnetars anywhere near us."
Len on 02.20.05 @ 07:40 PM CST