Get to know how your body could react to life in orbit with these 6 fun facts:
FIRST STOP: Astronauts Get Taller
The astronauts return to their preflight height after a few months of being back within the planet's gravity.
NEXT: Puffy Faces and Skinny Legs
For the first few weeks of spaceflight, most astronauts appear to have a puffy head and skinny legs. The fluid in their bodies redistributes evenly when gravity isn't playing a role in their biological systems. After a little time in orbit, however, the body adapts to the new distribution of fluids, and the astronauts don't appear as puffy.
NEXT: Coordination Trouble on Earth
Sometimes, spaceflyers will drop things, forgetting that gravity is influential back on Earth. After six months in microgravity conditions, it is difficult to adjust to life in a place where materials fall if you drop them.
NEXT: Muscle Meltdown
Although this might be ideal in space, it's problematic once back on Earth. Astronauts have to exercise for two hours a day on the space station just to maintain a healthy amount of muscle mass that they will need once they are back on the planet.
NEXT: My Aching Bones!
There are two treadmills and two stationary bicycles on board the space station to help the residents keep in shape during their time in orbit.
NEXT: Tossing and Turning in Space
The flashes are actually from cosmic rays — high-energy particles that beam through the solar system — shooting through the orbiting outpost. Spaceflyers have described the flashes as "fireworks" or "streaks." Although the radiation from the cosmic rays can build up over time, the particles don't pose too much of a risk during the limited time that astronauts spend on the station.
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