Changes

During the early days of NASA's space missions, Paul C. Fisher of the Fisher Pen Co set about developing a better pen, which could deal with the known problems of writing in space.

During the early days of NASA's space missions, Paul C. Fisher of the Fisher Pen Co set about developing a better pen, which could deal with the known problems of writing in space.

<ref>https://history.nasa.gov/spacepen.html</ref>

<ref>http://www.spacepen.com/</ref>

Since the design of the original space pen, few functional changes have been made.  For example, the Astronaut Space Pen (which is still sold today)<ref name="spacepen.com">http://www.spacepen.com/</ref> is very similar to the one used

<ref>http://www.gentlemanstationer.com/blog/2017/3/21/pen-review-the-fisher-space-pen</ref>

 

<ref name="NASA Spacepen">https://history.nasa.gov/spacepen.html</ref>

<ref name="spacepen.com">http://www.spacepen.com/</ref>

<ref name="gentlemanstationer.com">http://www.gentlemanstationer.com/blog/2017/3/21/pen-review-the-fisher-space-pen</ref>