A recent study revealed that spaceflight although does not consistently alter upper eyelid position, it does lead to a significant elevation of brow position. In simpler words, gravity has a more pronounced effect on brow position than it does eyelid position.
In the study, Justin Karlin, University of California, Los Angeles, CA, and colleagues aimed to describe the effect of spaceflight on upper eyelid and brow position.For this purpose, the researchers collected images of astronauts on earth and in space from a National Aeronautics and Space Administration image library. The researchers obtained front-facing portraits captured within a 5-year period for each astronaut. At least 6 photos were collected per astronaut, 3 taken on earth, and 3 in zero gravity.
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