Adapting back to Earth g

Bloomberg said it can take up to four weeks for astronauts to adapt to Earth's gravity after long space missions. He's working with the National Space Biomedical Research Institute to create a training system to speed up that transition. Astronauts walk on a treadmill with a moving base, while watching a projected image that's also moving. He simulates the astronaut's shaky balance by tilting the treadmill or the image they're watching.


He said that astronauts can adapt to the zero gravity of space in just a few days. But the readjustment to Earth depends on the length of the mission. Short-duration flights can take three to four days, while a six-month stint on the International Space Station can take four weeks.

Fascinating stuff. I’ve been reading about astronauts’ return to Earth, probably because I’m still curious about Mark Watney’s return to earth despite the lovely epilogue we were treated to in the movie, not to mention I watched a video on YouTube where two cast members of The Martian talked to astronauts currently in the International Space Station.

This recount is particularly interesting.

But we have to remember of course that while the Hermes in The Martian would have been mostly weightless while they accelerated through space, there were still spinning sections where gravity was simulated by centripetal forces that allowed the crew to sit at tables, and put down a cup without it flying away. Seems like a very fine line there between too much and too little force. At any rate, this would help them with adjusting to Earth gravity, I would warrant.

Mark on the other hand, had been living in Mars gravity for about 18 months. Mars gravity is only 38% of the surface gravity on Earth. He would probably have time to get used to Earth gravity again on the trip in Hermes, but would it be more difficult for him to adjust, I wonder? Perhaps not, given the heavy EVA suit he had to wear so much of the time, but then the recount above speaks of things such as suddenly realising you can feel your eyeballs have weight. Scary stuff.