According to the Baylor College of Medicine, there are several ways prolonged time in space can affect the human body. Advert Barry Wilmore and Suni Williams have been stuck in space since June 2024 (MIGUEL J. RODRIGUEZ CARRILLO/AFP via Getty Images) From your bones losing density and experiencing decreased muscle mass, to decreases in blood volume, orthostatic tolerance, and aerobic capacity – too much time in space can cause detrimental effects. Another cause for concern is space radiation. Exposure can cause astronauts to have radiation sickness, central nervous system effects, and degenerative diseases. In addition to this, space radiation causes 'increased lifetime risk of cancer'. The impact on their bodies when back on Earth A previous study involving identical twins Scott and Mark Kelly saw Scott head to space for almost a year, while Mark stayed on Earth. Advert When he returned, they compared the differences between them, with Scott's almost year-long mission in mind. One thing that Scott experienced after returning home was heightened sensitivity and a rash for around six days after he returned from the space station, BBC News reported; something which Williams and Wilmore may experience as well. The study involving the Kelly twins also found that Scott's DNA was affected by his space travel. Researchers analyzed the difference between twins Scott and Mark Kelly (ROBERT MARKOWITZ/NASA/AFP via Getty Images) Advert Scott's telomeres (the protective caps at the ends of chromosomes that prevent them from fraying or tangling) were found to have become 'significantly longer' during spaceflight, but once he returned to Earth, they shortened rapidly. Having shorter telomeres can increase a person's aging process and can be associated with increased risk of developing certain diseases. Telomeres naturally shorten with age, but 'astronauts in general had many more short telomeres after spaceflight than they did before [space travel]', said Susan Bailey, a professor of environmental and radiological health at Colorado State University, who was part of the study that looked at the Kelly twins. Featured Image Credit: NASA