Re: The Extinction Challenge
Sun, 1 Aug 1999 01:49:15 EDT

In a message dated 7/31/99 21:44:17, wrote:

>I don't need to check the calculations of your theory, I know you're wrong
>because it doesn't fit the facts. As I already said, the 1987 supernova
>produced about 20 neutrinos in one second that were detectable in one of
>our primitive neutrino observatories, and it was not close, it was in
another galaxy.
>The best the sun could manage is 1 or 2 a month. I don't want to be
>impolite but this is not a gray area, I'm right and you're wrong.

But even by your figures, a 100 kg mass would expect 2 x 10^7 hits from a supernova 2 ly away. In a body of many billions of cells, that's quite trivial. Only about 1 cell in a 1000 will take a hit, and the vast majority of hits don't do anything significant. A lethal dose of radiation needs enough
for most cells to take multiple hits to their DNA. This is still many orders of magnitude short. I'll bet an X-ray does far worse although I don't have figures in the house. It takes a lot of photons, even X-ray, to make an image.