[ExI] Fish in space

[Adrian Tymes]

On Sun, Mar 19, 2017 at 5:53 PM, John Clark <johnkclark at gmail.com> wrote:
> My hunch is that very short very intense
> exposure is more dangerous than much less intense exposure over a much
> longer time even if the number of millisieverts
> is the same, but it's only a hunch.
> What's clear is the radiation harm-function is far from linear.

The body has some ability to deal with malfunctions, such as cancerous
cells, that could in theory be expressed in units per time, as could
the damage from radiation.  At very small damage rates, the amount
that exceeds the body's capacity is small, perhaps zero.  At high
damage rates, the amount is so small that the ratio of damage
inflicted to damage observed might start to seem linear.

That's one hypothesis, anyway.

>> Otherwise, at 2.4 per year, you'd reach your lifetime cap in about 42
>> years - and many, many people live to well past double that.
>
> Yes, and maybe that's one reason old people are more likely to die than
> young people, or maybe not.

Yes, but by that math you'd expect a dramatic increase around 42, but
this is not seen until decades later.

Still, that could be one selling point for a space colony with
abundant radiation shielding: "More shielded than Earth = less
radiation per year!  Come here and live longer!"

(Granted, that assumes urban-Earth-normal access to things like health
care, such as 1-10 hospital beds per 1,000 people.)