Will Columbia Disaster Embolden Nuclear Protesters

Plutonium 239, the most efficient fissile material, is an alpha
emitter, which can be shielded by a couple of sheets of paper.
Enriched Uranium (98%+ U-235) fuel, used in nuclear submarine cores,
can be handled by hand prior to first going critical, because of the
shielding provided by the fuel cladding. Spent fuel will kill you
in minutes.

Ice Pilot

--- In ssi_list@... "victoriatangoman
> > I'm not arguing one way or the other, but I think the safety
> question is a
> > valid one. I am interested to hear why you or others believe
that
> a
> > nuclear-powered device breaking up on launch would not be a
health
> risk.
> > (And if not, have we just found a better solution to dealing
with
> our
> > nuclear waste than burying it under Yucca Mountain for a few
> million
> > years?)
>
> For a nuclear powered deep space vessel, which would never see
> atmospheric operation, I would imagine that the fissile material
> that is launched would not be "hot." The reactor components are
> assembled in orbit and then the U-235/U-238 etc is launched in a
> special casing that can survive explosion and ground impact.
>
> The key is that they're not launching a functioning reactor, which
> has many radioactive parts that can contaminate the environment.
>
> The engineering challenge is thus reduced to designing a casing
that
> can survive disaster. Even if you have to dedicate a whole shuttle
> cargo bay to lifting a casing whose mass or volume exceeds its
cargo
> by orders of magnitude. You can have multiply layers which
collapse
> as they absorb shock, compression, impact and other disaster
related
> stresses.
>
> That said, I believe this type of operation is completely
different
> from launching used radioactive material into orbit.
>
> An expert's opinion would be helpful on this question: is there
less
> radioactivity in fissile material that hasn't gone opertional yet?
I