Why Do Astronauts Use Space Pens Instead of Pencils?

Public Domain, Flickr
Public Domain, Flickr / Public Domain, Flickr
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by Alex Carter

It's often said that NASA spent millions of dollars developing a pen that could write in zero gravity, while the Russians just used pencils. It was a warning about looking for a high-tech solution to a mundane problem, of American excess vs. Russian sensibility.

It's also entirely false.

To understand why NASA was so keen on a workable space pen, you have to understand that the pencil is not suited for space travel. The problem is that they have a habit of breaking, shattering, and leaving graphite dust behind. The wood, too, can make it a serious fire risk in the pressurized, oxygen-rich capsule. All of these common issues become life-threatening hazards in space.

Still, there were attempts to bring pencils into space. In 1965, the agency famously ordered 34 specially designed mechanical pencils in hopes of finding the perfect writing tool for astronauts. But at $128 each, they weren't exactly cheap, and it only got worse when the public got wind of the price. Thankfully, an alternative was not too far behind.

Astronaut Walt Cunningham, pilot of the Apollo 7 mission, uses the Fisher Space Pen while in flight.
Astronaut Walt Cunningham, pilot of the Apollo 7 mission, uses the Fisher Space Pen while in flight. / NASA

The Space Pen was invented by Paul Fisher, head of Fisher Pen Company. Unlike a typical pen, the Fisher Space Pen uses compressed nitrogen to force ink out of the nozzle, instead of using gravity to make it flow. This made it the ideal device for writing in space, while upside down, or submerged underwater. It wrote crisp and clean, without the safety concerns of a pencil.

Fisher contacted NASA to give his pens a try in 1965 and in 1967, after months of testing, they were impressed enough to bulk buy 400 of them for future missions. Contrary to those urban legends, NASA didn't commission the pen or contribute any funding to it. The Soviets soon ditched their grease pencils and were eventually buying the same Fisher pens as NASA, too. The price? After a 40 percent discount from Fisher, both space agencies were paying $2.39 a pen.

The Fisher Space Pens made their debut in 1968 on the Apollo 7 mission and have been involved in all manned missions since.

So, the short reason is that astronauts only used pencils when they were waiting for something better to come along. As soon as it did, they switched and never looked back. Even the Russians thought it was a good idea.

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