The “Twin Study,” and What it Does and Does Not Say About The Health Hazards of Space Travel

  When Buzz Aldrin became the second man to ever walk on the moon, his lunar escapades, along with those of Neil Armstrong,  were a cause of national and pretty much global joy, wonder and pride.   That the mission was hazardous was self-evident -- from launch to the ad-lib and hair-raising landing on the moon, …