Serious question

[cbabe]

6. The eyes have it! Scientists focus in on how microgravity changes astronaut vision

https://www.space.com/microgravity-vision-effects-astronauts

The eyes have it! Scientists focus in on how microgravity changes astronaut vision

By Leonard David published April 2, 2023

After decades of collecting data about how astronauts' vision is affected by spaceflight, scientists have identified a set of microgravity-induced changes to the human eye known as Spaceflight-Associated Neuro-Ocular Syndrome, or SANS. This condition is considered a risk to human health in long-duration spaceflight.

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Overall, clarity over vision issues in space has come a long way since the February 1962 flight of Mercury astronaut John Glenn. That first three-orbit spaceflight by an American had Glenn dutifully monitoring his vision by reading an eye chart to see if his eyeballs might change and alter his vision.

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(Something I never thought of.)