Did a Hypernova Cause a Mass Extinction Event?

Now here is something interesting in an article I read on the IO9 blog. The article asks the question: Was an exploding star responsible for one of Earth's a mass extinctions" As attractive as it might be, there really is not a way to prove the supposition.

One event is question is particularly troubling: The Ordovician Extinction of 450 million years ago. Though not as famous as the K-T event which wiped out the dinosaurs 65 million years ago:

• the Ordovician was still plenty bad, driving more than 60% of all marine species extinct and since nearly all complex life still lived in the sea back then, that was particularly devastating

The really weird thing about the Ordovician event is that it was made up of two separate extinction events, the first was most likely caused by massive volcanic activity, but the second, a million years later: 

• defies easy explanation, and the quest to explain this mystery has led a small group of scientists to put forward a radical hypothesis: it was all caused by a gamma-ray burst. Specifically, this burst must have come from a massive stellar explosion known as a hypernova - an explosion at least a hundred times more powerful than the average supernova - that happened about a thousand light-years away.

Physicist Wilfred Domainko  says that the gamma-ray burst most likely came from a globular cluster.  Now that would be convenient because one of the jobs of the Gaia Star-Mapper, a European Space Agency probe due to start work in 2013, will be among other things, plotting globular clusters with hopes of finding one that may have been close enough in the distant past to have caused the Ordovician extinction even.

This article is really fascinating as well as having links to other article.  You can read the complete article on IO9  HERE