Changes

==Problem==

==Problem==

Before this pen was developed, there were some issues with fine writing.  Traditional [[pen]]s depended somewhat on gravity, and even though ballpoint pens were self-contained, the ball could run dry while writing.  Extreme temperatures, and even wet surfaces were also concerns.  Pencils were the obvious choice, therefore, since they are durable, reliable and cheap.  However, those didn't come without issue either. The graphite tip could break off, but even more problematic was the dust released into the air while writing.  Without the affects of gravity, dust and debris poses a real threat to on-board equipment.  Therefore, felt-tipped markers were often considered a safer option.<ref name="NASA Spacepen">https://history.nasa.gov/spacepen.html</ref><ref name="spacepen.com">http://www.spacepen.com/</ref>

Before this pen was developed, there were some issues with fine writing.  Traditional [[pen]]s depended somewhat on gravity, and even though ballpoint pens were self-contained, the ball could run dry while writing.  Extreme temperatures, and even wet surfaces were also concerns.  Pencils were the obvious choice, therefore, since they are durable, reliable and cheap.  However, those didn't come without issue either. The graphite tip could break off, but even more problematic was the dust released into the air while writing.  Without the affects of gravity, dust and debris poses a real threat to on-board equipment.<ref name="gentlemanstationer.com">http://www.gentlemanstationer.com/blog/2017/3/21/pen-review-the-fisher-space-pen</ref> Therefore, felt-tipped markers were often considered a safer option.<ref name="NASA Spacepen">https://history.nasa.gov/spacepen.html</ref><ref name="spacepen.com">http://www.spacepen.com/</ref>

==History==

==History==

==Variations==

==Variations==

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 during the early space program.<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>

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 kind taken to the moon in 1969.<ref name="gentlemanstationer.com">http://www.gentlemanstationer.com/blog/2017/3/21/pen-review-the-fisher-space-pen</ref>

==References==

==References==