It may look like a space-based disco but this mellow astronaut “dance” is actually an important pre-spacewalk procedure.
Thomas Pesquet of the European Space Agency and NASA’s Shane Kimbrough conducted their latest spacewalk aboard the International Space Station (ISS) on Friday, June 25, in which they installed the second of six of new solar arrays as part of ongoing work to upgrade the station’s power system.
But before leaving the interior of the ISS, Pesquet and Kimbrough appeared to perform a little dance (below) while fully kitted out in their spacesuits.
In a Facebook post on Friday, Pesquet jokingly described the sequence as a “spacewalk dance” before offering a more complete explanation of the brief boogie.
“We were not really dancing but purging our bodies of nitrogen,” the French astronaut said. “We breathe pure oxygen and slowly all the nitrogen in our bodies is replaced by oxygen, which is safer when going from high pressure (Space Station) to low pressure (spacesuit). Mild exercise makes us breathe more oxygen and gets rid of the nitrogen quicker.”
Pesquet added: “Also, it is fun to dance.”
Spacewalk dance! Happy to have finished #spacewalk season for the moment with success. Deserves a little dance. 😊 We were not really dancing though, but purging our bodies of nitrogen! 🕺 #MissionAlpha https://t.co/AJ7YPYugPD pic.twitter.com/Ab6pFSVeKB
— Thomas Pesquet (@Thom_astro) June 26, 2021
Elaborating on the procedure, NASA explains on its website that astronauts climb into their spacesuits several hours before a spacewalk is due to begin, with the suits pressurized and filled with pure oxygen.
Inside their spacesuits, the astronauts breathe the oxygen to rid their body of nitrogen that could lead to the formation of gas bubbles in their bloodstream and tissues when they exit the orbiting outpost.
“These gas bubbles can cause astronauts to feel pain in their shoulders, elbows, wrists, and knees. This pain is called getting ‘the bends’ because it affects the places where the body bends,” NASA said, adding, “Scuba divers can also get the bends.”
An alternative way for an astronaut to expel nitrogen is to spend a period of time in one of the space station’s airlocks, the compartment located between the main part of the ISS and space. The cabin pressure is then reduced in the airlock, enabling astronauts to safely rid their body of nitrogen prior to exiting the station.