Astronaut Scott Kelly set a record for the longest single spaceflight in history and now NASA is saying the trip made him a "new man" as well. So they made a decision to run some tests and compare Scott's DNA to his brother's after spending some time in space, and they were pretty surprised by the results.
One-Year Mission & Twins Study The two astronauts began their year in space on March 27, 2015, and returned to Earth on March 1, 2016. Scott (right) spent a year in space while Mark (left) stayed on Earth as a control subject. At present, astronauts only spend six months on the International Space Station as standard. So researchers tested both brothers before, during and after Scott's year in space to map specific changes in the astronauts' physical and mental health. They looked at various proteins and evaluated the twins' cognition as part of the overall study.
The Twins Study Investigators came from around the country to meet and share their final research results at the annual Human Research Program Investigators' Workshop held in Galveston, Texas in January 2018. "This is thought to be from the stresses of space travel, which can cause changes in a cell's biological pathways and ejection of DNA and RNA", researchers added. Some changes returned to baseline within hours or days of landing, while a few persisted after six months.
While Scott Kelly's height and 93 percent of his DNA returned to normal after returning to Earth, NASA confirmed that seven percent of his genes have remained changed and may stay that way. The space agency added that Kelly had hundreds of "space genes" activated by the year-long flight which reportedly altered the astronaut's "immune system, DNA fix, bone formation networks, hypoxia, and hypercapnia".
The individual studies on the twins will be combined into a summary paper, as detailed in the graphic above.