1. A Pencil Writes in Space, but Its Leftovers Float Around the Cabin
Writing is not the problem. A ballpoint pen needs ink to run down toward the tip, and a cheap one struggles when held upside down or against a wall. A pencil has no such need. The trouble is what a pencil leaves behind. [1]
On Earth, a snapped-off tip or a pinch of pencil dust drops onto the desk. In weightlessness nothing falls, so these bits drift through the air, along with wood shavings after sharpening. Reports on the topic list the dangers as a broken tip becoming a floating hazard for crew and equipment, tiny flecks of graphite getting lodged in delicate machinery, and wooden pencils, which are flammable. [1] [2]
That makes two separate worries. What exactly is each one, and how serious was it?
2. Graphite Conducts Electricity and Wood Burns: The Two Worries
The first worry is electrical. Graphite, the "lead" in a pencil, conducts electricity. Microscopic particles that find their way into delicate equipment could, in principle, cause trouble. [1]
The second is fire. In 1967 a fire during a ground test of the Apollo 1 spacecraft killed three astronauts, and NASA became especially careful about anything flammable on board, including wooden pencils. [3] [4]
One honest limit: the articles describe these as hazards that could happen. None of the sources I read names a case in which pencil dust actually broke a spacecraft system. Even so, weightlessness removes the usual cleanup, which is why a small risk got taken seriously. So what did crews use instead, and why did a pencil end up in the news?
3. The "Expensive Space Pen" Story Really Began with an Expensive Pencil
In 1965, NASA ordered 34 mechanical pencils for Project Gemini, its second crewed spaceflight program. The bill was $4,382.50, which works out to about $129 per pencil. [4]
When the price became public, there was an outcry. A US congressman from New York, John Wydler, wrote to NASA's head, James Webb, asking for a full investigation and an explanation of why the cost was justified. NASA's answer, as the historian Dwayne Day tells it, was that the pencil housings were made of lightweight, strong material and enlarged so astronauts could use them in bulky gloves. The writing mechanism inside had cost only $1.75. [5]
So the first "too expensive" scandal was about a pencil, not a pen. Where did the pen come from, then?
4. A Pen Company Paid for the Space Pen Itself
Paul C. Fisher ran the Fisher Pen Company. His company reportedly invested about $1 million in a pen that could work without help from gravity, and none of that money came from NASA or Congress. Fisher patented the design in 1965. [4] [3]
The design has two main parts. The ink cartridge is sealed and filled with nitrogen gas under pressure, about 35 pounds per square inch (roughly 240 kilopascals). The gas pushes the ink toward the tip. And the ink is "thixotropic": almost solid while it sits still, then turning liquid where the spinning ball rubs against it. NASA's own article says Fisher's earlier pressurized cartridge leaked, and that he succeeded once he added resin to the ink. [2] [4]
NASA did its part by testing. Its testing center found the pens worked in every position, in extreme heat and cold, and from pure oxygen to vacuum. [2] Because of the pencil row, NASA was cautious at first, but after tests it chose the pen. The Fisher pen first flew with the Apollo 7 crew in October 1968, and has gone up on NASA crewed missions since. [4] [2]
That leaves the second half of the joke. What did the Soviets use?
5. Checking the Legend: Both Space Programs Used Pencils, Then Bought the Same Pen
The legend says NASA spent years and a fortune on a pen while Soviet cosmonauts used a pencil. The fact-checking site PolitiFact rated it False. [3] Putting the records together, three things differ from the story:
Who paid: A private company paid for developing the pen, not NASA or Congress. [3] [2]
Who used pencils: At the start, American astronauts and Soviet cosmonauts both used pencils. [3] (One of the sources adds that NASA did briefly look into a space pen of its own, but dropped the idea once costs began to climb. [1])
Who bought the pen: In 1969 the Soviet Union ordered 100 Fisher pens and 1,000 ink cartridges for its Soyuz flights. According to Scientific American, NASA and the Soviets paid the same bulk price, $2.39 per pen instead of $3.98. [4] [3]
Sources disagree: PolitiFact also says NASA paid $6 per pen for about 400 pens in 1967, while Scientific American cites a February 1968 report of $2.39. I have not settled which is right, so the safe summary is "a few dollars per pen." Either way, a pen cost a small fraction of the roughly $129 mechanical pencil. [3] [4]
Why did the story spread? The sources suggest it makes a neat contrast: a wasteful government on one side, a simple solution on the other. [5] That is my interpretation, not a proven cause.
6. What Do Astronauts Write With Today, and How Can You Test the Idea at Home?
The International Space Station is not a pencil-free zone. According to ScienceAlert, crews there have pens, markers, and mechanical pencils. A NASA astronaut explains the pencils are handy because you can erase when procedures change, and the station's air filters help clear stray debris. [1] NASA's article adds that Space Pens have flown on every crewed NASA mission since Apollo 7, with dozens aboard the station. [2]
You can try a safe version at home. Write a dark patch on white paper with a pencil, then gently tilt the paper and watch the dust slide off. Now picture that dust staying in the air instead. Please do not blow or tap the dust into the air. Next, hold an ordinary ballpoint pen pointing up and try to write. Whether it works depends on the pen, and that is exactly the problem the pressurized cartridge was built around.
If you want to dig deeper, the NASA Spinoff article tells the pen's story from the company's side, and the PolitiFact and Space Review pieces show how the legend was checked. Reading them, you can compare the prices yourself.