The Fisher Space Pen is a ballpoint pen that will write upside down, underwater, over grease, and in extreme cold and hot temperatures. This pen has an estimated shelf life of 100 years.
After rigorous testing, in 1967, NASA selected the Fisher Space Pen for use on the Apollo Missions. They are now used on all manned space flights – American and Russian.
The apocryphal story that NASA spent all this time and effort to make a pen that works in space – while the Russians instead chose to use a #2 pencil, is in fact, just that – apocryphal. That said, like most stories of this kind, it rings true – as it reflects the philosophies of the two programs to a “T”.