The Moon is ten times higher than the Van Allen radiation belts. The spacecraft moved through the belts in just 30 minutes, and the astronauts were protected from the ionizing radiation by the aluminium hulls of the spacecraft. In addition, the orbital transfer trajectory from the Earth to the Moon through the belts was selected to minimize radiation exposure. Even Dr. James Van Allen, the discoverer of the Van Allen radiation belts, rebutted the claims that radiation levels were too dangerous for the Apollo missions. Dosimeters carried by the crews showed they received about the same cumulative dosage as a chest X-ray or about 1 milligray.[51] Plait cited an average dose of less than 1 rem, which is equivalent to the ambient radiation received by living at sea level for three years.[42], pp. 160–162
The radiation is actually evidence that the astronauts went to the Moon. Irene Schneider reports that thirty-three of the thirty-six Apollo astronauts involved in the nine Apollo missions to leave Earth orbit have developed early stage cataracts that have been shown to be caused by radiation exposure to cosmic rays during their trip.[52] However, only twenty-four astronauts left earth orbit. At least thirty-nine former astronauts have developed cataracts. Thirty-six of those were involved in high-radiation missions such as the Apollo lunar missions.[53]