If you’ve seen Gravity – Alfonso Cuaron’s mesmerising latest film – you’ll understand the terror.
If not, it’s this: a storm of space debris hits a space shuttle mission, obliterating the craft and sending astronaut Ryan Stone (Sandra Bullock) plummeting, spinning uncontrollably into empty space. Subsequently cast adrift, with no support craft, Earth 400km away and only crewmate Matt Kowalski (George Clooney) for company, it’s truly a thing of nightmares.
Few of us can comprehend the loneliness of the vacuum of space, but one man who has an inkling is Tom Jones, a Nasa astronaut and veteran of four space shuttle missions. With three space walks that total more than 19 hours under his belt, as well as being a key participant in the construction of the International Space Station, he’s been right where Clooney and Bullock are pretending to be. Here, he explains what it’s like to walk in space, the dangers of space walks – called EVAs by Nasa (Extra Vehicular Activities) – and what he thought of Gravity.
How does it feel to step out into space? It’s wonderfully liberating to go out on your own, and manoeuvre with your fingertips, and work while free from the sensation of gravity. At the same time, you’re getting this stunning view of your spaceship, and the space station and the universe around you. It’s a fantastic experience. I worked very hard to get my space walk, and I worked very hard during my space walks, but you can’t be a human being and go out there and not take the time to be just awed by the opportunity to see that view and experience space in a way that just a few other people ever have.
Is the human mind prepared to take on the context of that view? I don’t think you’re overwhelmed by it, I think you’re impressed as a professional would be, but if you do take some time to let the experience sink in, that’s when it really starts to get to you emotionally. Remember that you get well prepared for it. I trained for hundreds of hours underwater, to get the sensation of the suit moving in weightlessness, so you sort of understand how your suit’s going to move. And in a spaceship in orbit, looking out the window, you get a sense of how the Earth looks and the sky looks but then you put those two things together and they add up to a lot more than the pieces themselves.
The added dimension is that it’s very quiet, you don’t have two or three people chatting around you, getting their work done. You’re by yourself, and all you hear is a little radio chatter. There’s a sense of solitude and independence, and the view through the helmet visor is vast and humbling.
Do astronauts who’ve done a space walk get extra bragging rights that those who haven’t don’t? Everybody’s very satisfied and proud of the fact that they’ve done a space walk. They are looked up to by the other astronauts as people who have actually accomplished that. Most people want to have that experience, and they are eager to hear about it. When you’re in the water training with someone who’s been on a space walk, and you haven’t, you really watch what they do to make sure that you get the moves down and that you understand their approach. One of my mentors was a guy named Story Musgrave who was on the first Hubble telescope repair mission. I remember the advice he gave to us novices as an experienced space walker. He said: “You know, you should treat this as a ballet dance. You should be out there, dancing on your fingertips for six or seven hours. And moving very carefully with grace and with efficiency. Don’t waste your muscular energy and don’t waste movements. If you find yourself working too hard, and struggling and sweating while outside, stop. You’re doing it wrong. If you’ve got the technique down, you’re going to glide through this and do it with very efficient, gentle moves. If you’re trying to hurry, it’s going to take you longer.”
Your three space walks. Did they all go to plan? When I went out from Atlantis at the space station, on my very first space walk, my fellow astronaut Bob Curbeam and I encountered a coolant leak from one of the lines that we were connecting to the new laboratory that we had installed with the rest of the crew. When ammonia coolant started venting out of one of these hoses, showering Bob with snowflakes of toxic ammonia, it was venting into space like a comet tail. That was a rare, but not completely unforeseen, failure, but yet we knew the system, and the engineers had discussed with us what we might do to stop such a leak.
Bob very coolly remembered all of those conversations and moved quickly within five minutes to cut off the flow of ammonia coolant. We only lost only about 5 per cent of the coolant amount before he got it shut off. Working together, we were able to get the cooling line connected properly. It was a mechanical failure that was due to a sticky valve that was stuck partially open in that cold vacuum of space.
We overcame that with some quick thinking on his part and then working together with mission control to come up with a procedure to get it sealed properly. So that was really a curveball thrown at us, and Bob was coated with ammonia frost which meant we had to plant him in the sunshine for an entire orbit to let the sun bake this toxic ammonia coolant off his space suit. It was very unusual – startling – to have that kind of a failure.
Are you aware of the terrifying and murderous vacuum an inch away from your nose, constantly? You get that sense of danger back on the earth when you are practising in your suit and they put you in an altitude chamber and pump the air out to simulate the low pressure at up to 400,000ft (122km) of altitude.
They put a pan of water in the air lock and you watch this water boil away furiously. It turns into vapour in the low pressure. They tie off a surgical glove in the same chamber and it swells up to the size of a pumpkin. This graphic display of the difference in pressure between inside your comfortable suit and outside, where there’s this harsh vacuum that could kill you in a few seconds, is sobering. When actually on a spacewalk, I don’t think I ever thought about the vacuum around me. Too busy.
Another exercise they put you through in the altitude chamber on the ground is opening up a valve on the side of your helmet to purge carbon dioxide and water vapour from your suit. You open it and you can actually see through a little hole about 2mm in diameter, into the vacuum outside. It’s a very interesting sensation – to deliberately open that valve. The air whistles out; the suit can’t sustain that for very long. You don’t do that actually on the space walk unless there’s an emergency, but that demonstration of how the suit can still function, even if the fan breaks down or your electrical power has gone away, prepares you for dealing with those eventualities in space.
Did you ever let go? In all of my space walking, I never let go of the spaceship without being attached by some mechanical means. You’re holding on to a handrail, you have your feet in foot restraints, like Sandra Bullock’s character in the film’s trailer, and you’re always tethered to the spaceship because that’s a safety measure you pay religious attention to. You do not want to drift away, even though you have an emergency jetpack to fly back to the ship. You don’t want to activate that and lose 30 minutes of your space-walking time when you have so many goals to accomplish.
What did you think when you heard that an EVA had been given it’s own film? I was excited that I’d be able to share the spacewalking experience, EVA, with a wide audience. If the movie was done well, then perhaps my audience and friends could get some sense of the exhilaration I felt outside.
Have you seen Gravity? And did you find any faults with it? I have seen Gravity, twice. I enjoyed it just as much the second time, picking up many more details of the movie, and sizing it up for accuracy. Its survival story is compelling, and is a visual treat. I truly enjoyed the ride that Gravity provided. I laughed at the mistakes and shortcuts with physics, but it didn’t detract from the excitement and suspense of the movie for me.
The movie greatly simplifies the complex orbital mechanics required to scoot from one orbit or spacecraft to another; the movie’s heroine would never make it doing what is shown. And our spacesuits are not as rugged as shown in the film. The impacts and bumps sustained would rupture a suit’s fabric – a very bad ending to the story! And I wondered what happened to the astronauts who left a Soyuz capsule behind at ISS (they could not all fit in the other one), and in the abandoned Chinese station. How did they get home? There are never spare or excess lifeboats at a space station, it’s too expensive.
Can an actor ever really capture what it’s like to space walk? Clooney’s jetpack antics are laughable, because of danger to the Hubble, the shuttle, and to himself. But we accept this unreality because it moves the story along.
Are female astronauts any different to work with than male ones? Space crews know each other so well they can practically read each others minds. That comes from years of training and socialising. The unfamiliarity of Clooney with Bullock’s character is another element of the film that makes astronauts smirk. Women astronauts work and train and perform just like the other crew members. Yes, we make allowances for privacy in space, but all other duties are shared equally. The women don’t want to be treated differently, and at Nasa, they are not.
Tom’s book, ‘Sky Walking: An Astronaut’s Memoir’ is available at Amazon.co.uk.
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