53-year-old astronaut Scott Kelly shared a dramatic excerpt from his new book Endurance: A Year in Space, A Lifetime of Discovery
in the Brisbane Times
, describing his first 48 hours back on earth and what he'd learned on the mission:
I push back from the table and struggle to stand up, feeling like a very old man getting out of a recliner... I make it to my bedroom without incident and close the door behind me. Every part of my body hurts. All my joints and all of my muscles are protesting the crushing pressure of gravity. I'm also nauseated, though I haven't thrown up... When I'm finally vertical, the pain in my legs is awful, and on top of that pain I feel a sensation that's even more alarming: it feels as though all the blood in my body is rushing to my legs, like the sensation of the blood rushing to your head when you do a handstand, but in reverse. I can feel the tissue in my legs swelling... 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...
Our space agencies won't be able to push out farther into space, to a destination like Mars, until we can learn more about how to strengthen the weakest links in the chain that make space flight possible: the human body and mind... [V]ery little is known about what occurs after month six. The symptoms may get precipitously worse in the ninth month, for instance, or they may level off. We don't know, and there is only one way to find out... On my previous flight to the space station, a mission of 159 days, I lost bone mass, my muscles atrophied, and my blood redistributed itself in my body, which strained and shrank the walls of my heart. More troubling, I experienced problems with my vision, as many other astronauts had. I had been exposed to more than 30 times the radiation of a person on Earth, equivalent to about 10 chest X-rays every day. This exposure would increase my risk of a fatal cancer for the rest of my life.
Kelly says the Space Station crew performed more than 400 experiments, though about 25% of his time went to tracking his own health. "If we could learn how to counteract the devastating impact of bone loss in microgravity, the solutions could well be applied to osteoporosis and other bone diseases. If we could learn how to keep our hearts healthy in space, that knowledge could be useful on Earth." Kelly says he felt better a few months after returning to earth, adding "It's gratifying to see how curious people are about my mission, how much children instinctively feel the excitement and wonder of space flight, and how many people think, as I do, that Mars is the next step... I know now that if we decide to do it, we can."