NASA's ‘rescue mission’ for Sunita Williams to launch today. Here’s why prolonged stay at space is life-threatening

NASA is in the final stage of preparing for the launch of its SpaceX Crew-9 mission on September 28 from Cape Canaveral Space Force Station in Florida. This mission is crucial for bringing astronauts Sunita Williams and Butch Wilmore safely back to Earth after their extended stay aboard the International Space Station (ISS) since June. 

Originally, Williams and Wilmore travelled to the ISS in June on Boeing’s Starliner capsule for an eight-day mission, but their stay was extended due to issues with the Starliner’s thrusters. 

The unscheduled stay in space threatens the life of Williams and Wilmore, who have to maintain strict regime to reduce the harmful impact of space on their bodies. 

Here is why a prolonged stay in space is life threatening for humans: 

Radiation 

According to NASA, space radiation is one of the most hazardous aspects of spaceflight. Outside Earth’s protective magnetic field and atmosphere, the ionizing radiation in space will pose a serious risk to astronauts.  

High-energy galactic cosmic rays, which are remnants from supernovas, and solar storms like solar particle events and coronal mass ejections can harm the body and spacecraft. 

When astronauts travel in space, they can’t see or even feel radiation. However, this radiation can damage DNA and lead to cancer, cataracts, and radiation sickness. 

Gravity 

Astronauts' entire bodies – muscles, bones, inner ear, and organs – must adjust to the new gravities encountered on the space station or their spacecraft, as well as on the Moon, Mars, and Earth once they return home. This can cause physical discomforts like back and abdominal pain.  

Without the continuous load of Earth’s gravity, weight-bearing bones lose on average 1% to 1.5% of mineral density per month during spaceflight. Water and other fluids in the body shift upward to the head, which may put pressure on the eyes and cause vision problems.  

If preventive measures are not implemented, crews may experience an increased risk of developing kidney stones due to dehydration and increased excretion of calcium from their bones. 

Isolation 

Astronauts are isolated and confined in a small space for long periods of time, which can lead to behavioural changes. The possibility of equipment failures or medical emergencies, and a critical need to ration food and supplies, astronauts must be capable of confronting an array of situations with minimal support from teams on Earth. 

Ecosystem maintenance 

Maintaining a safe ecosystem inside a spacecraft presents unique challenges, from ensuring optimal temperatures, pressures, and lighting, to reducing noise, monitoring microbial communities, and tracking immune responses. The ecosystem inside a spacecraft plays a big role in the daily life of an astronaut in space. 

Microbes can change characteristics in space, and micro-organisms that naturally live on the human body are transferred more easily from person to person in closed habitats, such as the space station. Stress hormone levels can elevate and the immune system can alter, which could lead to increased susceptibility to allergies or other illnesses.