From: OPIK, Lembit
Sent: 28 July 2003 09:40
Subject: RE: Asteriod statistice
Just realised you never got a reply to the e-mail. Sorry.
I can't get to the figures straight off, but I'll explain the working out which is as follows.:
While the possibility of dieing from impact strike in any year is low, the catastrophic nature of the impacts is so large that the actuarial risk is relatively high. From memory,if we get hit by something big enough to wipe out 25% OF THE EARTH'S POPULATION every 100,000 years, then, in actuarial terms there's a 1 in 400,000 chance of being wiped out by a cosmic strike in any year - or a 1 in 5300 in an average UK lifespan. It's millions to one against winning the UK National Lottery in any weekend, assuming one ticket is bought. The figures worked outgas a differential probability of 750. Happily,the Government's Near Earth Object Taskforce concurred with this figure,and it appeared in their report.
So, the Key thing to remember is Actuarial Risk.. And the key assumptions are frequency of major impact and extent of fatalities.
Sorry again for the delay, and hope this helps. Incidentally, loads more info available on the Spaceguard website, and by accessing the Govt report on www.nearearthobjects.co.uk
All the best,
Lembit Opik MP