Originally Posted by antoniseb

If you are worried about this pair, there are some reasons not to worry:
- in 85 million years we will probably be much further from this pair, as that is more than a third of a galactic orbit.
- short GRBs are most likely highly directional with their projected energy.

That doesn't mean that such a scenario isn't a risk in the billion year time-frame, or rule out this as the cause of the Ordovician extinction. I'd be interested in reading more about any evidence about the OE that suggests this kind of event as the cause.