Cosmic Radiation

On Tuesday, September 23, 2003, at 03:12 AM, victoriatangoman wrote:

> Then it occured to me that this "Earth blocking" feature presupposes
> that the Earth's atmosphere on the other side of the world doesn't
> exist. If the atmosphere above your head blocks the radiation, so
> too does the atmosphere down under. T

The effect of the blocking from atmosphere 'down under' is trivial
compared to the blocking by 6,000 miles of rock. The reason you need
double the atmosphere is that I assume *no* cosmic radiation comes from
under your feet on Earth. Thus, on a colony, you get cosmic radiation
from twice as many directions, requiring twice the shielding provided
by the atmosphere.

The materials in one asteroid (the largest ) are sufficient to make
orbital space colonies with ~150 times the surface area of the Earth in
usable real estate. See http://lifesci3.arc.nasa.gov/SpaceSettlement/
for details.

Al Globus
CSC at NASA Ames Research Center
http://www.nas.nasa.gov/~globus/home.html

Views expressed in this email are only my opinions and are not the
position of any organization I'm familiar with.