Neil deGrasse Tyson Quotes

People do really well on space missions, but it's the physiological, the medical stuff, the stuff like radiation, loss of bone mass and muscle mass and density. It's those things that we need to figure out.

The microgravity or the very, very low amount of gravity that we have up in space forces some changes in different processes. It forces changes in us as human beings.

Gravity on Earth provides a force that keeps our bones and muscles working. In the microgravity of space, our bones and muscles are not taxed, so they begin to atrophy.

The workouts have positively impacted the astronauts' bones and muscles, and they are coming back in really good shape. But some are losing bone and muscle but not as much as we saw in the early days.

One thing we've learned about space is that the human body starts to fall apart after relatively short exposures to microgravity.

National Osteoporosis Awareness and Prevention Month is celebrated each May, and becomes a chance for our Nation to become more familiar with the effects of this disease, and about the preventable steps that we can take to deal with it.

I lost more then 6 kilograms when I ceased with the top sport. That were all muscles. They are now gone.

Intervention for the prevention and control of osteoporosis should comprise a combination of legislative action, educational measures, health service activities, media coverage, and individual counselling to initiate changes in behaviour.

Adaption of the human body in space is not yet mastered. As soon as you hit space, you feel your body is going through a period of mutation. There's no blood in your head; you have a hard time swallowing. We're not born to naturally be in space.

When you talk to crews that went to Mir or have gone up to International Space Station, they say that you go through different phases of adaptation or getting used to the space environment.

Just like the bones and muscles, the heart is designed to work in one gravity here on Earth, so when you put the heart in space, it operates differently and changes shape.

During my time in orbit, I lost bone mass, my muscles atrophied, and my blood redistributed itself in my body, which strained my heart. Every day, I was exposed to ten times the radiation of a person on Earth, which will increase my risk of a fatal cancer for the rest of my life.

The one thing we can't really train for is weightlessness, real weightlessness. It's a ton of fun. It's pure Newtonian physics. You push in one direction, you go in the opposite direction with an equal force.

Man is not made for space. But with the help of biologists and medical doctors, he can be prepared and accommodated.

Exercise is very important, first of all if you think about it, especially in a long flight like a six month space flight and on the ISS. If you didn't exercise and used the analogy on earth, it would be like laying in bed. So, just imagine laying in bed for several months, and even just trying to get up and walk, you probably wouldn't be able to. But if you got up and you exercised two hours a day, you'd probably be okay, and that's the same in space.

Other anatomical changes associated with long-duration space flight are definitely negative: the immune system weakens, the heart shrinks because it doesn't have to strain against gravity, eyesight tends to degrade, sometimes markedly (no one's exactly sure why yet). The spine lengthens as the little sacs of fluid between the vertebrae expand, and bone mass decreases as the body sheds calcium. Without gravity, we don't need muscle and bone mass to support our own weight, which is what makes life in space so much fun but also so inherently bad for the human body, long-term.

The great thing about the Island is you've got room. You can go for a bike ride. We're 20 minutes to a beach, and you can get on the beach and go for a long walk.

Your arms don't hang by your side in space like they do on Earth because there is no gravity. It feels awkward to have them floating in front of me.

The calluses on your feet in space will eventually fall off. So, the bottoms of your feet become very soft like newborn baby feet. But the top of my feet develop rough alligator skin because I use the top of my feet to get around here on space station when using foot rails.

Something people don't recognize is that being on the space station is probably a lot like being in some kind of confinement - like isolation.

I do Pilates. And that's best for me... because I can't really do any other sports any more because of my muscles.

It's crazy how fast you get out of shape if you miss a couple days of action.

I have a pretty high metabolism rate. So I tend to lose muscle mass if I am not working out.

Sequencing DNA on the ISS will enable NASA to see what happens to genetic material in space in real time, rather than looking at a snapshot of DNA before launch and another snapshot of DNA after launch and filling in the blanks.

After floating for nine and a half months in space, gravity is not your friend.