In 1965 NASA purchased 34 mechanical pencil units for a total cost of $4,382.50.  That’s not exactly watching your pennies and there was a public outcry over this cost.  Paul Fisher, of Fisher Pen Co., then designed a pen that would write in zero gravity using a pressurized ink cartridge.  It is also supposed to write underwater, in extreme temperatures, and through a stick of butter.  That’s kind of strange, but I guess it’s good for bakers.  He made his pen without any funding from NASA.  Then he sold it to NASA.  However, they were careful not to spend too much for the pen.  In 1967 they bought 400 pens for $6 each.  The Soviet Union also bought the pens.  The good news for Fisher is that he put a patent on the pen and NASA continues to use them.

There is an urban legend about NASA spending millions to develop this pen while the Soviet Union just used pencils.  Well, now you know the real story.  Another interesting tidbit: if the pencil broke in space, it became a floating hazard!  The lead could fly into someone’s eye or into an instrument on the craft.