Astronaut Scott Kelly Describes One Year In Space -- And Its After Effects (brisbanetimes.com.au)

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."

Comments

Why we can't go to Mars... yet

[knorthern knight]

https://www.youtube.com/watch?...

tldr;

* only 40% of missions have actually succeeded, i.e. not crashed

* microgravity will render astronauts helpless. I.e., unlike earth, there won't be anybody at the destination to carry you off on a stretcher and treat you back to health. (Bone loss and vision changes/glaucoma, low blood pressure, T-cell reductions). You need a rotating setup for centripital gravity.

* a piece of rock the size of a beebee can wreak enormous damage to the ship; think Apollo 13

* radiation; a solar flare would be fatal to astronauts.Van Allen belts mostly protect against charged particles. If a flare hits a mission outside the Van Allen belts, the astronauts will die eventually, unless the mission carries literally tons of lead shields. The moon missions were lucky to not get hit. A Hohmann transfer orbit takes approx 6 months to get from earth to Mars (or visa versa). You will get hit by solar storms

If we could get an "ion-drive" to get us there in a month, that will cut down the the bone loss, and exposure to radiation.

Re:sigh .. the centrifical effect

[hawguy]

The first intermediate step which we are fully capable of doing is creating a much larger space station to use as the jumping off point for other missions into the solar system. The most expensive and dangerous piece of manned space travel is getting out of the gravity well. We have enough available lift capacity to move construction supplies, man power, and the supplies need to support human life.

That sounds like an expensive and wasteful way to prepare for space travel to an unknown destination and unknown timeframe with a spacecraft of unknown design. What supplies do you send? How do you know they'll be useful 10 years from now when you're ready to use them?

You could send water and assume it'll be used for *something*, but if you find a way to get it from an asteroid (or from the moon) you may have wasted a lot of fuel and space launches when you could have been launching aluminum I-Beams for construction. Oh, but when you're ready to build your ion-jet spacecraft, you find that you've launched beams that are much too heavy for the task. Or you're using hydrogen-oxygen engines and now you've found that you underestimated the strength needed.

The most expensive and dangerous piece of manned space travel is getting out of the gravity well

Launching those supplies ahead of time doesn't make it easier to get out of the gravity well. Finding the supplies you need outside of the gravity well does.

Re:This issue is Real

[turp182]

A couple of Nat Geo issues ago there was an article where a scientist said, due to lower gravity on Mars, we would become taller with more thin arms and legs, after only a couple of generations (maybe a single one if born there). Due to the lower gravity.

It would seem someone BORN on Earth would probably suffer health problems on Mars (given what zero gravity does, it isn't hard to conclude that lower gravity would cause issues), it would be interesting to see someone BORN on Mars grow up though.

Nat Geo's website sucks, I couldn't find the relevant info (my goodness, it's all about the TV channel). It was interesting.

You Troll, but there is a kernel of Truth

[sycodon]

Of course there is no "anti-gravity" but there is a way to create gravity...centrifugal force.

This is so well know I won't even explain it. The engineering has already been done on this at NASA and it's not really that big of deal, although it calls for a more expensive, complex and larger space craft.

It is obvious than humans were not designed for a weightless environment and longer space missions to Mars or anywhere else will require a rotating work/living space.