Uploaded on May 6, 2013
The Five (Main) Senses in Space: Sight
2013-05-07 - Flattened eyeballs? Random flashes of light? CSA Astronaut Chris Hadfield explains how vision is altered during spaceflight. Part 2 of 5 videos on how the main senses are affected in space.
(Credits: Canadian Space Agency, NASA)
TranscriptChris Hadfield: Some astronauts, on long-duration spaceflights, have reported having blurred vision. And scientists think it may be caused by the extra fluids in our head, resulting in a sort of a flattening of the eyeballs, and maybe even swelling around the optic nerve, which creates a shift in our prescription, in our vision. The swelling of the optic nerve seems to resolve over time. But the flattening of the back of the eye, we're not sure, but it doesn't appear to return to normal, even after we return to Earth. An other strange effect is a sensation of seeing flashes of light when our eyes are closed. It's caused by cosmic rays that can be seen as bursts, or stripes, or even stars. Some astronauts are more sensitive than others, and they can detect them, even in the daylight.
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