If humans are ever going to make it to Mars, we need to understand how it will affect our fleshy little bodies. That’s why Scott Kelly and Mikhail Korniyenko were sent up to the International Space Station (ISS) in 2015 as part of the One-Year Mission (even though it was actually for 340 days).
As Kelly explains in his new book Endurance: A Year in Space, A Lifetime of Discovery, his body was fraught with problems after his long-stint in space. So much so, he believes it was easier to spend nearly a year in space than to get used to gravity again back on Earth. One of the most taxing challenges to initially overcome was remastering the simple skill of walking.
“I push back from the table and struggle to stand up, feeling like an old man getting out of a recliner.” Kelly wrote in his book.
“I start the journey to my bedroom: about 20 steps from the chair to the bed. On the third step, the floor seems to lurch under me, and I stumble into a planter. Of course, it wasn’t the floor – it was my vestibular system trying to readjust to Earth’s gravity. I’m getting used to walking again.”
The vestibular system, mainly located deep within your inner ear, helps to control your sense of balance and spatial orientation. As you can imagine, floating around in microgravity for a year can disorientate this system, so it takes time for it to readjust to the conditions on Earth. On top of that, walking is made even harder because of muscle wastage, even though you exercise extensively while up on the ISS.
Kelly also explains how he woke up in the middle of the night in severe pain with swollen legs and painful rashes on his skin.
“I make it to the bathroom, flip on the light, and look down at my legs. They are swollen and alien stumps, not legs at all,” he wrote.
“I use the bathroom and shuffle back to bed, wondering what I should do. Normally if I woke up feeling like this, I would go to the emergency room, but no one at the hospital will have seen symptoms of having been in space for a year. “
You can also check out a video of Kelly on The Verge that shows him attempting to walk for the first time back on Earth after nearly a year in space. It's from the new PBS documentary Beyond A Year In Space. You can also watch a video of Kelly being lifted out of the Soyuz TMA-18M spacecraft just after it landed in Kazakhstan.