mozel (@why man can't go to the moon, right away) ID#20637: (なぜわれわれは、今すぐに、月に行くことができないのか)
• Many scientists have also questioned how the astronauts could have survived passing through the intense radioactivity of the Van Allen radiation belts. By some estimates, protection from the belts - thousands of feet wide - would have required a solid envelope of lead some four feet thick.