Astronauts Scheduled for a Spacewalk To Explore the Exterior of International Space Station, Check for Surviving Microorganisms

Astronauts usually conduct a spacewalk mainly for maintenance purposes outside the International Space Station (ISS). In the next spacewalk, two astronauts will carry out another mission that could help us understand life outside of Earth.

Potential Life in Outer Space

The exterior of the International Space StAtion is known to be extremely hostile to living organisms, with temperatures reaching up to 248 to -148 degrees Fahrenheit (120 to -100 degrees Celsius). Aside from it, this environment also lacks atmosphere and receives extreme levels of solar radiation.

For many years, experts have been investigating "extremophiles," or the organisms which can withstand extreme environmental conditions. These include tardigrades, the eight-legged micro-animal which is known to survive prolonged periods of time outside the Earth.

Earlier experiments conducted outside of the ISS have revealed that smaller bacteria and microorganisms are capable of withstanding extreme environmental conditions for years. This possibility hints that other parts of the Solar System, such as Mars, may be capable of sustaining life.

Search for Extremophiles

On June 13, Tracy Dyson and Matt Dominick are set to venture outside the orbital post to check if samples of microbes attached to the exterior have survived. Astronomers believe that Dyson and Dominick will have a higher chance of encountering samples that are still teeming with life.

According to the paper "Survival of microorganisms during two-year exposure in outer space near the ISS," scientists discovered certain species of bacteria and fungi which thrive on cotton wool fixed to metal rods outside of the International Space Station. They were found to survive even after two years of getting exposed to outer space.

The study authors suggest that dehydration and freeze-drying in the vacuum of near-Earth space could be the main reason why these microorganisms were able to survive for a long period of time. In another study entitled "DNA Damage and Survival Time Course of Deinococcal Cell Pellets During 3 Years of Exposure to Outer Space", a team of Japanese experts discovered that a type of bacteria known as Deinococcus radiodurans can last for up to three years in outer space.

These studies are just ample evidence that microorganisms can indeed withstand a lack of atmosphere, extreme temperatures, and harmful solar radiation. With the help of astronauts like Dyson and Dominick, humanity can be one step closer to understanding how these microbes are able to survive, possibly helping us on our search for extraterrestrial life.

The two astronauts have other missions for their spacewalk other than checking for the survival of microbes. They are also tasked with the removal of a faulty electronics box from a communications antenna on the International Space Station.

According to NASA, Dyson and Dominick will exit the Quest Airlock to complete the removal of the radio frequency group on the starboard truss of the space station. Their mission can be watched live starting from 6:30 a.m. EDT (4PM IST) on June 13. It will be streamed on NASA Television, NASA+, YouTube, the NASA app, and NASA's website.

The spacewalk will start at 8 AM and will last about six and a half hours. Once the two astronauts complete the spacewalk, NASA aims to schedule US spacewalks 91 and 92 on June 24 and July 2.