European Space Agency astronaut Alexander Gerst performs an eye exam for the Ocular Health experiment which observes and seeks to understand vision changes during long-term space missions on the International Space Station June 3, 2014 in Earth Orbit.

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European Space Agency astronaut Alexander Gerst performs an eye exam for the Ocular Health experiment which observes and seeks to understand vision changes during long-term space missions on the International Space Station June 3, 2014 in Earth Orbit.

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Size: 3427px × 5150px
Location: Earth Orbit
Photo credit: © NASA Photo / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: america, astronaut, cevis, cosmonaut, crew, esa, experiment, german, iss, mission, nasa, science, spacecraft, technology, testing, usa, vertical, working