the origins of the twins study were not within NASA Human Research. Scott Kelly suggested the idea himself.Related:
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Both did badly in school, and Scott struggled more than Mark. Both were quickly bored. But both conceived an implausible desire to become astronauts
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They found a backdoor into naval aviation through ROTC at the Merchant Marine Academy (Mark) and the State University of New York Maritime College (Scott). At college, they discovered they were highly intelligent engineers—perfect scores in calculus came easily now that they had a goal—and in the Navy they landed jets on carriers and became test pilots. Mark flew in combat during the Gulf War.
They were both selected as astronauts in the class of 1996.
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Scott got dumber on the ISS, but he stayed dumber, too. The decline in the speed and accuracy of his mental functions persisted six months after his mission.
"Chinese scientists have put human brain genes in monkeys—and yes, they may be smarter"
"The first privately funded mission to the Moon has crashed on the lunar surface "