[ExI] Radiation damage could stop manned trips to Mars

[BillK]

On 11 October 2016 at 21:45, Stephen Van Sickle  wrote:
> Yes, it does.  It matters quite a bit.  If you live in Denver for 80 years,
> your total background dose is abut 1 Sv.  Any effect of that won't be
> measurable.  If you get that dose in one hour, you will show symptoms of
> Acute Radiation Syndrome and have about a 5% chance of dying from it in a
> month.  Rate likely will have a different effect with cosmic radiation than
> with gamma, but a blanket statement that "rate of dosage doesn't matter" is
> just plain wrong.
>
> I also said "take with a big grain of salt", not "disregard entirely".
> Heavy ion radiation is one of the two biggest medical concerns (the other
> being .38 g gravity effects).  It is a serious issue, but like .38 g just
> about impossible to experiment with on earth.  Even if there is an
> accelerator that can create cosmic ray energies (and there isn't), no one
> would tie it up for 2 or 3 years for one experiment.  So they do the
> experiment that they can, not the one which they need.  Very common, but the
> results are rarely definitive.
>


That was bad wording from me.

The experiment used very low doses of charged particles and found that
impairment continued up to 24 weeks after exposure (i.e. no recovery).
Neither the rats nor the astronauts would be exposed to acute
radiation syndrome.

BillK