Not that I WANT to terraform Mars...

From: "Bill"
To:
Sent: Friday, July 20, 2001 2:57 PM
Subject: [spacesettlers] Re: Not that I WANT to terraform Mars...

The Earth normal assumption is what the 10 m thick shield was designed
for. In fact the design requirement was half the radiation level in
Denver Colorado. I'm not sure why by the way. I also don't remeber it
being 10 m. Are you sure it was 10 m and not 10ft? The study I
normally quote is the AMES study that brought out the Standford Torus
as the design.

According to a geographic atlas that I'm checking just now, Denver seems to
be located in a very high place (over 3 Km?); hence, they have less passive
shielding from the atmosphere, like anyone living in high mountains or
plateaus (e.g., in the Andes). The fact that people living there do not have
remarkably high cancer or mutation rates is an indication that the radiation
level is ok even though it is higher than at sea level. So, in the AMES
study, they assumed a passive shield equivalent to the one provided by the
atmosphere in high places.

Yes, I remember that in the AMES study the thickness of the shield was 4
meters or so (about 12 feet - close to your 10 feet figure). I mentioned a
radiation shield 10 m thick because this thickness would provide, I think,
about the same shielding that people have at sea level (assuming a linear
relation between thickness and shielding). Again, a case of "more than
enough shielding".

[snikt]
Bill
[snikt]

Lucio