The US space agency NASA said that astronauts Sunita Williams and Butch Wilmore might have to wait till February 2025 to return to Earth. A technical snag in the spacecraft that took them to the International Space Station (ISS) has forced them to spend an extended period in space.
- The ISS can comfortably house them for the next six months. Currently, there are seven other astronauts at the space station.
- The International Space Station (ISS) is a permanent space laboratory orbiting Earth at a distance of about 400 km. It is continuously manned and has never been without an astronaut since November 2000.
- NASA has increasingly been deploying its astronauts for extended stay missions to study the impacts on human bodies.
- US astronauts flying to the ISS can now volunteer to be part of such experiments.
- NASA is running a programme to study the impacts of short routine (up to eight months), and extended stays (more than eight months) of astronauts in space.
- The human immune system has evolved under Earth’s gravitational force. Consequently, in the microgravity environment of space, immune function is altered.
- According to NASA, microgravity is the condition in which people or objects appear to be weightless. The effects of microgravity can be seen when astronauts and objects float in space.
- “Micro-” means “very small,” so microgravity refers to the condition where gravity seems to be very small. Microgravity is sometimes called “zero gravity,” but this is misleading, says NASA.
- According to reports, due to the longer exposure to microgravity on the ISS, astronauts might experience several health-related issues such as bone density reduction, vision-related issues, and are also at a higher risk of cancer due to DNA damage.
- Low gravity impacts brain fluids and extended stays can potentially alter brain structure. Extended stays can also increase the risk of heart disease.
- This is why space exploration missions are kept short, not lasting more than a few weeks.
(Sources: Indian Express and NASA)
