Golden Shields

George did say that he wasn't thinking of space colony
shielding when he brought up Gold, he was thinking
about spacesuits. For something like that one
obviously cannot use several thousand kilograms per
square meter of surface area.

That got me thinking about spacesuits in general. The
have a use within the earth's magnetosphere, where the
earth's magnetic field itslef provides some of the
shielding. However, for use in places like the
asteroid belt I can't see spacesuits (at least, the
type we are used to seeing now) being used.

Instead, I think that for such an application we
should consider 2001-style pods: a sphere no more than
a couple meters in diameter with a couple of
manipulator arms. These have big advantages,
particularly for spacewalks lasting several hours.

For one, comfort: an astronaut could do things like
scratch his nose in a pod. The interior could be at a
constant pressure, with no worries about joint
stiffness causing limited mobility. The astronaut's
fingers and toes wouldn't get cold like they do on
today's spacesuits. An astronaut's finger's wouldn't
get fatigued from simply trying to hold onto tools;
those would be handled by the manipulator arms, and
the astronaut wouldn't have to be fighting interior
pressure all the time.

And, the radiation shielding on the pod could be much
thicker than on a spacesuit. This is where a
combination of George's Gold idea and my assertion
that lower atomic weight material would be better
could be tried. Imagine the pod being made of
multiple layers from the outside in: a layer of Gold
foil on the outside, then a thin aluminum hull, then a
layer of polyethelene a couple centimeters thick, then
a layer of Gold foil, then a layer of polyethelene,
then a layer of Gold foil, then a layer of
polyethelene, etc. The hull/radiation shield would
end up being say 20 centimeters thick, and the
different properties of the Gold and the polyethelene
layers would stop both the high-energy and the
secondary radiation.

Ed