How eyesight is affected in space

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Chris Hadfield on how eyesight is affected in space

To better understand how vision is impacted in the space environment, astronauts use onboard medical instruments like the tonometer to examine the health of eyes. Commander Chris Hadfield gives us an inside look at these instruments and demonstrates how they work. Credit: CSA/NASA

For more about living in space, visit: http://www.asc-csa.gc.ca/eng/astronauts/living.asp

Source: Canadian Space Agency - YouTube Channel