The Eyes Have It! Focus on Microgravity Impact on Astronaut Vision

There are microgravity-induced changes to the human eye tagged as Spaceflight-Associated Neuro-Ocular Syndrome, or SANS for visual brevity. This condition is considered a risk to human health in long-duration spaceflight.

Polaris Dawn crew members (left to right): Anna Menon, mission specialist and medical officer, Scott Poteet, mission pilot, Jared Isaacman, mission commander, and Sarah Gillis, mission specialist.
Image credit: Polaris Program/John Kraus

Later this year, a SpaceX Falcon 9 rocket will hurl the Polaris Dawn mission of four crew members skyward for a privately-backed voyage of up to five days in Earth orbit. During their stay time circuiting our planet in a Crew Dragon capsule, the high-flying team is dedicating major time to probe health impacts on the body from their sojourn into space.

Little was known regarding vision in Earth orbit when Mercury astronaut, John Glenn, circuited the Earth in 1962. He gauged his visual status by reading an eye chart mounted on the instrument panel of his single-seat capsule.
Image credit: NASA

Mercury capsule instrument panel with eye charts.
Image credit: Dane Penland/Smithsonian National Air and Space Museum (Used with permission)
Image credit: NASA

One of their medical tasks is specific to help unravel what’s behind SANS symptoms. It is a known, unknown issue, say researchers, a malady that includes swelling of the optic nerve, alteration in the shape of the eye itself, as well causing fuzziness to vision. Clearly, on any lengthy trek to Mars and back, being “blindsided” by blurry eyesight from SANS is not ideal.

For more information, go to my new Space.com article – “The eyes have it! Focus on microgravity’s impact on astronaut vision – Clearly, on any lengthy trek to space and back, being “blindsided” by blurry eyesight is not ideal – at:

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