06-18-2013, 08:30 AM
It's notable that alpha, beta, proton and neutron radiation are quite effectively shielded by low atomic weight materials such as carbon, also. I believe the reason is that in the case of these radiations, the closer the nuclear mass is to the mass of the incoming particles the more momentum is transferred. This is IMHO relevant, because of the likely use of carbon-based nanomaterials for structural components means that you're lugging around lots of carbon anyway.
To stop gamma and X-rays a reasonably small amount of lead or similar might do, at least in environments similar to that around Sol. The real problem is heavy ions in cosmic rays; although lead might stop those quite well you then get lots of secondary particles. For that reason, IMHO if you're going to line your ship with something heavy the best place for it is probably on the outside.
One more point: For habitats and long-duration ships in low-tech (by OA standards!) polities, you're going to need quite a lot of crushed mineral (i.e. dirt) to grow your crops (and leisure plants such as trees) in. A couple of metres of dirt would double quite well as a shield.
Just my 2 cents.
To stop gamma and X-rays a reasonably small amount of lead or similar might do, at least in environments similar to that around Sol. The real problem is heavy ions in cosmic rays; although lead might stop those quite well you then get lots of secondary particles. For that reason, IMHO if you're going to line your ship with something heavy the best place for it is probably on the outside.
One more point: For habitats and long-duration ships in low-tech (by OA standards!) polities, you're going to need quite a lot of crushed mineral (i.e. dirt) to grow your crops (and leisure plants such as trees) in. A couple of metres of dirt would double quite well as a shield.
Just my 2 cents.