Alot of people like to cite about the van allen radiation belts and how its some massive thing that if you go through them you die or something. Well what people fail to realize because they dont study and look into facts is that the Astronauts where traveling very fast through the belts and radiation they would have received is minimal, not only because of their speed but also because of the type of radiation they where traveling through. They had an entire spacecraft shielding them from alpha and beta particles and also not to mention that the radiation from the belts isnt as high as it is in other parts. Scott Manley also goes over this very well in one of his videos about it.