Occasionally, astronauts at the International Space Station (ISS) step outside to work on the body of the ISS, spending hours in Earth’s orbit with nothing to protect them from the frigid vacuum but their spacesuits.
Click start to play today’s Spell It, where astronauts have to be ‘aware’ of everything that can go wrong, as they work in space.
According to the US space agency National Aeronautics and Space Administration (Nasa), there have been 267 spacewalks at the ISS since December 1998, and the longest one lasted for eight hours and 56 minutes on March 12, 2001. Astronauts usually have a to-do list when they head out on their spacewalk, and action items can include laying the groundwork for a new docking port for commercial crew vehicles, or putting on a thermal cover on certain devices or applying lubrication to a robotic arm – all while the space station zips around the Earth at 8km/h.
Here are some other facts about spacewalks to know, according to a November 2015 report in the National Geographic:
1. The spacesuits are old and often smelly
Spacesuits are expensive, and often have to be shared by different astronauts who live on the ISS for short periods of time. The spacesuits that astronauts wear on their spacewalk, for instance, are at least 35 years old. They’re difficult to clean because they’re filled with pure oxygen when in use – it’s so highly combustible, even lint from a towel could catch fire if it were left behind after cleaning. Needless to say, the suits can develop a smell – one astronaut even reportedly said it smelled like a locker room.
2. Astronauts feel incredibly hot and cold
Without the Earth’s atmosphere to protect them, astronauts have to bear the full effect of massive temperature fluctuations (of up to 500 degrees) during a seven-hour spacewalk. When the ISS is in the direct path of sunlight, it can get very hot very quickly, and when the sun goes out of sight, temperatures can be frigid. Since the ISS’s orbit around Earth takes about 90 minutes, it can see the sun rise and set every 45 minutes. Astronauts have commented in the past that the heat is often easier to deal with than the cold, since they can look for shade around the space station.
3. It’s not really walking
American astronaut Scott Kelly tweeted on October 29, 2015, that it should be called ‘spaceworking’ not ‘spacewalking’. It’s because astronauts spend a lot of time doing space ballet on fingertips – they have to propel themselves, stop, hold onto things, push off and stabilise themselves, all with the use of their hands and fingertips. In fact, their sorest muscles after a spacewalk are their hands and forearms, and they barely use their legs.
4. Mics are on
During a spacewalk, the astronauts’ microphones are ‘hot’, meaning everyone in mission control and watching the live feed can hear every breath they take and word they mutter. So, astronauts have to be careful what they say, even in moments when they’re frustrated!
5. It could always be worse
Astronauts are always communicating with each other, because they have a saying that ‘there’s nothing so bad in space that you can’t make it worse’. Being present in the moment, alert and aware is important to prevent mishaps. Even though astronauts train for emergency scenarios, like if a piece of space debris hits and tears an astronaut’s spacesuit, making it leak oxygen, not every potential danger can be anticipated. For instance, in a 2013 spacewalk, European Space Agency (ESA) astronaut Luca Parmitano’s helmet filled with water, blinding him as he felt his way back to the airlock. While any number of things can go wrong in space, the key is to rely on yourself and your team to get through.