While Scott was in space, his samples were sent back to Earth with shipments that had delivered supplies by rocket to the ISS.
The team collected physiological, telomeric, transcriptomic, epigenetic, proteomic, metabolomic, immune, microbiomic, cardiovascular, vision-related, and other data over 25 months.
For nearly a year USA astronauts and uniform twins Scott and Mark Kelly inhabited life as distant as Earth and space. Mark provided a baseline for observation on Earth, and Scott provided a comparable test case during the 340 days he spent in space aboard the International Space Station for Expeditions 43, 44, 45, and 46. The astronaut was supposed to spend a year on the ISS, and the space agency would compare his development to his twin brother on Earth.
Persistent changes were observed in a few other areas, including some cognitive function.
The study also presented three major findings.
Scott's telomeres noticeably increased in length in space (by 14.5 percent) but these changes weren't long-lasting and they returned to pre-flight measures within two days of his return to Earth.
"Our main findings in Mr. Scott were that the carotid artery wall became thicker early in flight and remained so throughout the mission", Dr. Stuart Lee of NASA's Johnson Space Center said.
"Changes described in this study highlight pathways and mechanisms that may be vulnerable to spaceflight and may require safeguards for longer space missions; thus, they serve as a guide for targeted countermeasures or monitoring during future missions" noted the authors.
Astronaut Scott Kelly made himself a guinea pig for all the people who dream of human journeys to Mars and other destinations in space. For example, the flu vaccine administered in space worked exactly as it does on Earth. Telomeres are the protective "caps" on the ends of chromosomes. These findings help demonstrate how a human body was able to adapt to the extreme environment of space and help researchers better understand how environmental stressors influence the activity of different genes, leading to a better understanding of physiological processes in space. According to the U.S. space Agency, Nasa, most of the differences that appeared during the time All disappeared, after the completion of the Mission - for example, changes in the gene activity. A small percentage related to the immune system and DNA fix failed to return to normal, however, indicating potential lasting damage at the genetic level.
"Radiation is much lower than what we expect it to be going to Mars", said Steven Platts, deputy chief scientist at NASA's Human Research Program.
Scott spent almost a year in orbit on board the International Space Station between 2015 and 2016 while his brother Mark remained on Earth. "The data captured from integrated investigations like the NASA Twins Study will be explored for years to come". Before, during, and after the one-year Mission, the two were examined again and again.
Cognitive tests before, during and after the flight found that Mr. Scott's cognitive performance declined post-flight in terms of speed and accuracy. The findings represent 27 months of data collection.
The research will help make astronauts and other space explorers stay safe on future missions. Principal investigators at NASA and at research universities across the nation initiated an unprecedented sharing of data and discovery.
The results of the current study, ten Teams consisting of more than 80 scientists spread over 12 universities developed. While significant, it is hard to draw conclusions for all humans or future astronauts from a single test subject in the spaceflight environment.
According to NASA, the study will provide a basis to assess the hazards of long-term space habitation.
"This paper is the first report of this highly integrated study that began five years ago when the investigators first gathered".