RE: Alpha Radiation [was Re: The Extinction Challenge (fwd)] (fwd)

Billy Brown (ewbrownv@mindspring.com)
Wed, 4 Aug 1999 14:57:18 -0500

hal@finney.org [SMTP:hal@finney.org] wrote:
> The neutrinos from supernova 1987A had energy 5 to 40 MeV. This is
> about 4 x 10^-5 ergs, or about 10^-7 calories. If this is deposited in a
> cell of size about 10 microns, the cell volume will be about 10^-9 cm^3.
> Depositing 10^-7 calories in 10^-9 g of water will raise its temperature
> by 100 degrees Celcius.

According to my usual on-line reference (http://calc.entisoft.com/scripts/UnitsCGI.Exe), the correct conversion here is 1 erg = 2.39 x 10^-8 calorie, not 10^-2. That gives you a temperature change of only 0.0001 degrees C.

Billy Brown, MCSE+I
ewbrownv@mindspring.com