Re: DINOSAUR CANCER

[Dalmiro Maia du DASOP <dalmiro@mesioq.obspm.fr>]

tuckr@digital.net wrote:

> >  Writing in the New Scientist journal, Collar suggests that a collapsing 
> > star
> > within 20 light years of earth could produce about 12 malignant cells per
> > kilogram (2.2 lb) of living tissue.
> 
>     Data?
> 
>     Countless tens of thousands of neutrinos are passing through you and me
> each and every second every day of our lives, including during the brief
> moments I've taken to type this and you've taken to read this (assuming you
> did). We exist in a sea of neutrinos.
> 

Well, the energetics of these neutrinos would have been different from those of
the Sun, so the cross-sections would be different also.

> > Other scientists have suggested that mass extinctions could be caused by
> > cosmic rays from supernova explosions, but Collar says these happen too
> > infrequently to explain the disappearance of the dinosaurs.
> 
>     Nine years ago this February, Supernova 1987a (in the Large Magellanic
> Cloud, a satellite galaxy of the Milky Way) sent an extra-large dose of
> neutrinos our way. Only about eleven (out of billions and billions) (Down,
> Carl!) were counted by detectors in the U.S. and Japan (*after* they'd
> passed *completely through* our entire planet).
> 

Since the space-density goes as the square of the distance the flux from
a 20 light-year supernova would be much higher. Though I don't believe on this 
results it would be fun to revise the calculations (they must be quite 
straightforward). Does anyone have better references? 

what I find really funny on this kind of news is that everybody thinks only on
dinos, they all seem to forget the mass extinctions that happened on smaller
taxa.