Have a geek moment with Beth Wilson, host of STEM in 30. She's taking a closer look at the spacecraft that helped John Glenn become the first American to orbit the Earth. Why were there eye charts in the spacecraft? Beth explains why. 

Created:

October 31, 2016

Source:

Smithsonian's National Air and Space Museum

Owner:

Smithsonian Institution

Rights Usage:

Contact Smithsonian Institution

Terms of Use:

Smithsonian Terms of Use

For print or commercial use please see permissions information.