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Why did NASA spend millions developing a pen that would work in space when a pencil is just as good?

Category: Space
Published: December 12, 2012

NASA did not spend millions developing a space pen. The first U.S. astronauts did indeed use pencils and not pens, according to the NASA History Program Office. After a private inventor (Paul Fisher) developed a space pen on his own, he attempted to sell the pens to NASA. At first NASA refused the offer. Pencils lead to unwanted dust in the confined quarters of a space ship, so NASA was searching for an alternative. Unfortunately, ordinary pens do not work in free fall conditions like the astronauts experience. On the surface of the earth, gravity accelerates the ink downward while the pen case is held in place by a person that is held in place by the ground. But in space, both pen and ink are steadily falling so that the ink does not come out. In contrast, Fisher's space pen uses internal pressure to force the ink out, much like an aerosol can. After testing Fisher's pen, NASA became so satisfied with their performance that it started purchasing the pens for $6 a piece. Russian cosmonauts also switched from pencils to Fisher space pens.

Topics: NASA, space pen, space pencil