Space expert reveals dangers Nasa's stranded astronauts can expect on rare spacewalk

Table of Contents

NASA's two "stranded" astronauts are set to venture out into space this week, having been stuck up there for over seven months longer than intended.

They'll leave the International Space Station for a surprise spacewalk on Thursday, which will be Butch Wilmore's first time venturing outside since his recovery flight last June malfunctioned.

Her partner Sunita Williams, who's now in command of the station and was only meant to stay eight days, will be doing her second spacewalk in roughly a week's time.

To check if microbes exist outside the station.

Fair dinkum, Butch and Suni are seen by some as space castaways, but they're top-notch professionals and will be tackling the mission every astronaut hopes for before their trip back to Earth next spring.

But what does a spacewalk or "EVA" for short, actually involve, and how dodgy is the task?

Spacewalks are like the 'toughest gym session' you could ever do on earth.

You're not just going to be admiring the view - you've got to be suited up in a heavy, bulletproof, pressurised suit, do some tricky movin's, and breathe compressed air for six to eight hours, all while goin' without tucker and with only a limited drink.

In addition to physical challenges, the psychological effect can be significant – particularly when you've been stuck at home for months.

Dr Lindsay said: ‘If you think back to how everyone was feelin' in 2020 when we were all locked down at home [durin' the Covid-19 lockdowns], how good was it when we were told we could go out for a bit of a stroll and get some fresh air at last?

‘Doing an EVA, a spacewalk, is the big Aussie-Yank equivalent.’

A lot of astronauts will tell you about the Overview Effect, which is a feeling of awe and a new perspective where you look at Earth against the blackness of space and suddenly see it as a small, fragile place.

‘I reckon that the first minute coming out of the ISS is gonna be wonder and excitement, but also professional stickability,’ Dr Lindsay said.

For Butch, it'll be his first time out in months and not just out, but floating in space.

Exploring life without gravity.

They'll likely have a more relaxed workload the day before, so they can rest up and get ready.

Before exiting the ISS, Suni and Butch will have to get used to much lower pressure than what they're used to, so they'll need to breathe 100% oxygen in a special airlock compartment to minimise the risk of getting decompression sickness, similar to what deep sea divers experience when nitrogen forms bubbles in their blood and tissues.

Once they're outside, they'll be in constant radio contact with their mate doing a spacewalk and with their mate inside, but will be working almost on their own.

Dryness of the body can become a major issue, as astronauts have limited access to water, making it difficult to replace fluids lost through excessive sweating.

Their heart rates will be kept under constant observation to make sure if they begin showing signs of stress, they'll be pulled back inside.

One of the main things NASA has to watch out for is motion sickness and dizziness, which can occur when astronauts leave the airlock.

“Getting a point of view of the globe from up high can change things,” Dr Lindsay said.

To battle this, a part of the ISS like a solar panel is swivelled so it's always in view below them so they've got something as a floor reference to anchor their vision: ‘You don't want to chuck up in a space suit.’

Astronauts Suni Williams and Butch Wilmore

Sunita Lyn ‘Suni’ Williams

• 59
• Scores of 7' and is not high; Seven has been achieved by a female an eight has been achieved by some, and that isn't a great score.
• Two days, four minutes and forty seconds

Barry Eugene ‘Butch’ Wilmore

• : 62

• 4

• Twenty-five hours and thirty-six minutes

Both blokes, being top pilots from the US Navy, are going toe to toe.

They took on the crewed mission of the Boeing Starliner in June 2024, but pulled out of space due to safety concerns.

They'll be heading back to Australia in a SpaceX Crew Dragon capsule, which'll land in the ocean with a splash.

Another concern is the existence of tiny meteoroids that might collide and penetrate the space suit.

The risk is shown by craters and holes found on the outside of the ISS at times, but there's never been an incident where one of these objects has actually hit an astronaut.

Tracking stations on earth keep an eye on every big space rock in the area, and the spacewalk is planned to avoid any that might get too close.

There's a crisis plan if an astronaut gets hit. The space suit is designed to seal up straight away around the area of impact so the damage remains confined.

It's also built to withstand impacts to start with, using heavy-duty Kevlar, as well as to safeguard against radiation.

'Doctor Lindsay reckons it's a real relief for blokes to get out of the suit,' 'They're always swelterin' cos they're workin' hard, so they've gotta dry the inside of the suit with a cloth.'

They'll take a break to eat, and up to the dunnies. Then they'll hang up their uniforms.

Fair dinkum, they'd've probably had to use the amenities during those spacewalks that went for six to eight hours.

If they had to do a weewee during the spacewalk, they'll have to deal with their Maximum Absorbency Garment (basically, a space nappy).

‘The rule is if you use it, you clean it up,’ Dr Lindsay said.

The day ahead will be a bit of a relaxing one, giving 'em a chance to recover while catchin' up with family and friends back home, and maybe getting in some gentle exercise to stay active.

Spacewalks which went wrong

Most spacewalks go off without a hitch, a reflection of the meticulous risk assessment and planning done beforehand – but some have had unexpected issues.

When Russian cosmonaut Alexei Leonov performed the first extravehicular activity in 1965, the crew hadn't realised that his spacesuit would expand in the vacuum of space.

It ballooned up so much he couldn't wriggle back inside the airlock, and his body temperature soared putting him at risk of heatstroke. He just managed to release some air and get safely back inside, and changes were made to space suits to stop this occurring again.

In 2013, Nasa astronaut Luca Parmitano nearly perished in space due to his spacesuit malfunctioning.

About 1.5 litres of water poured into his helmet because of a blocked filter, and he had to quickly make a beeline for the airlock as the liquid started trickling into his ears and nose.

While Suni and Butch weren't expecting to be stuck in space for so long, it's not overseas for astronauts to spend this much time on the ISS.

In fact, the length of time spent there is getting longer, Dr Lindsay said, because our ambitions for space travel are undergoing a change.

A home and workplace in orbit around the Moon is being developed at the Moon Gateway space station.

Reaching Mars is also a target, with Elon Musk hoping his Starship rocket will be the first one to make the trip.

‘Aussies will be spending longer and longer time in space,’ Dr Lindsay said, so it is essential we find out about the effects of long-term residence there.

An unplanned mission like the one Suni and Butch are currently working on will also give us valuable insights into how to handle missions that extend beyond Low Earth Orbit, like those to Mars, and maybe even further into space.

.

.