Although the answer "they passed through it very quickly" does not sound very scientific, essentially, that is exactly what happened. The Van Allen Belts, especially the lower belt, are very dangerous if you were to lingered within it's effects. Satellites have to be heavily shielded when their orbit places them in the belts for any length of time otherwise their circuitry would quickly be destroyed.
The Apollo astronauts receive relatively low doses of radiation because their route was specifically planned to avoid the belt, as much as possible, thereby reducing their exposure to tolerable levels.
Don't know too much about this, but I think the Van Allen belt is a bit like the earth;'s magnetic field. By that I mean it narrows right down and appears to enter into the earth a the poles. Maybe the rockets actually leave through a narrower window.
We know that the ionospheric layers, the Kennelly-Heaviside, and the Appleton layers begin to disintegrate and break down after the sun stops shining on that particilar part of the world. It is easier for a radio wave to penetrate right through and go off into space. There is a gradual reintegration of the atoms in those layers at night.
Maybe something along the same lines happens with the Van Allen belt but....frankly, I don't know.
I'm not an astrophysicist, but I will take an educated guess:From what limited information I could gather, the belt is described as "moderately dangerous" to humans. I am under the assumption that this means the exposure becomes lethal over an extended period of time. Since the Apollo astronauts were not exposed to cosmic radiation for very long, the effects they suffered were likely minimal (if anything at all).
Going to mars would take considerably longer, and astronauts would have months of exposure to the belt as opposed to days. The Van Allen radiation belt is *massive* - so they would have constant exposure to it over much of the duration of the trip.
I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.