>>10070332There are several types of radiation.
Alpha particles (basically high energy protons)
Beta particles (high energy electron or positron)
Gamma radiation (high energy photons)
Blocking alpha particles is as simple as a sheet of paper.
Blocking beta radiation can be done with anything electrically conductive, like tinfoil.
Blocking gamma or xray radiation is orders of magnitude more difficult, and literally requires several feet of concrete, or up to 15 feet of water.
Now, I am not a complete expert here, don't take my word as gospel. But I can surmise some things based on my knowledge of physics.
Radiation of all types is streaming off the sun, but most notably alpha particles. These types of charged particles find a bottleneck in the earth's magnetic field, and can release beta radiation, or gamma radiation as secondary decay products. So there might be a hotspot of these other types of radiation in the van allen belts.
Blocking alpha and beta radiation is....trivial. Even a spacesuit is enough to block it. The real issue I see is blocking the gamma radiation coming off the sun. This radiation is not in the form of charged particles, thus it's not being trapped in the van allen belts. But there is probably a small hotspot in the van allen belts from secondary decay. I suspect this effect would be very minor.
In the spaceship, you can probably block a lot of the gamma radiation (but not all of it), but during any sort of spacewalk you won't be. On the Moon as well, you are at the sun's mercy. I believe I read that a spacewalk is the equivalent of getting several chest xrays. Your cancer risk will increase because of that. But it's worth it to people in order to have that experience.
