NASA Astronauts' Eyesight Damaged by Long Space Flights

They knew they were in a risky business. But now, as American astronauts spend more and more time in space, they've noticed they're returning to Earth with a surprising malady: They cannot focus their eyes properly after they come home, and for some the problem seems permanent. Astronauts with 20/20 vision found they needed glasses for the first time, says NASA. A few, their names withheld to protect their privacy, were told it would be unwise for them to fly in space again. At least a...Full Story