Glass windows

On 14/08/06, Ed Minchau wrote:
> I sincerely doubt that 5cm of glass comes anywhere close to the radiation
> shielding of 5 meters of slag.

As noted by others you only need about 50cm of radiation shielding;
about 3 tonnes/m^2.

Note that for an Island 3, the radiation situation is rather better
than you would expect- the atmosphere above you acts as a respectable
shield. The density of the air is about 1kg/m^3, so if the diameter is
20km, you have 20km of mass thickness from above you which is 20
tonnes/m^2, and this is a pretty respectable radiation shield.

So the glass is irrelevant, apart from when you are standing right
next to a window; (it might be worth having radiation walls near to
the window section, or landscaping or something.)

Other than that so far as I can see, lateral radiation would be
shielded due to the thicker path it would take through the hull, and
your surroundings/buildings would reduce it further.

There probably would be the highest radiation from right underneath
your feet through the hull, but that's a relatively small angle, so
the radiation presumably isn't too bad.

Hope this helps.

> Ed
>
> --- "Combs, Mike" wrote:
>
> > From: spacesettlers@yahoogroups.com
> > [mailto:spacesettlers@yahoogroups.com] On Behalf Of
> > Ed Minchau
> >
> > > --- "Combs, Mike" wrote:
> > > > Is there a perception that glass panels in a
> > steel frame are
> > > > inadequate to the task? O'Neill calculated that
> > such could be
> > > > engineered at the scales of the three "Island"
> > models of space
> > > > habitat. Engineering for a glass-paneled
> > pressure hull of more
> > modest
> > > > diameter would be simpler still.
> > >
> > > Beware of little boys with slingshots.
> >
> > Little boys with slingshots can hardly damage glass
> > 5 cm thick. Pull
> > out a ruler and try visualizing that.
> >
> > This relates to my earlier writings that I think the
> > reason why some
> > people see windows as a problem to be avoided at all
> > costs is because
> > they conceptualize the windows of a space habitat as
> > having the same
> > characteristics as the windows in their house,
> > instead of thinking in
> > terms of the actual specifications given. We don't
> > have much common
> > experience with the characteristics of slabs of
> > glass 5 cm thick.
> >
> > Regards,
> >
> > Mike Combs
> >

--
-Ian Woollard

"Victory can be perceived but not created."
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