Can't astronauts use ball point pens in space?

Question

Is it true that astronauts can't use ballpoint pens in space? The mechanical contact of a ballpoint with the paper should make the ink show up on paper but I'm not sure if it's true.

Any clarification will be greatly appreciated.

Answer 1

They can and they do use regular ballpoint pens as well as normal pencils, mechanical pencils, grease pencils, felt-tip markers ("Sharpies"), and pressurized "space pens".

ESA astronaut Pedro Duque comments on ballpoint pens in his 2003 diary.

I am writing these notes in the Soyuz with a cheap ballpoint pen. Why is that important? As it happens, I've been working in space programmes for seventeen years, eleven of these as an astronaut, and I've always believed, because that is what I've always been told, that normal ballpoint pens don't work in space.

During my first flight I took with me one of those very expensive ballpoint pens with a pressure ink cartridge, the same as the other Shuttle astronauts. But the other day I was with my Soyuz instructor and I saw he was preparing the books for the flight, and he was attaching a ballpoint pen with a string for us to write once we were in orbit. Seeing my astonishment, he told me the Russians have always used ballpoint pens in space.

...I also took one of our ballpoint pens, courtesy of the European Space Agency (just in case Russian ballpoint pens are special), and here I am, it doesn't stop working and it doesn't 'spit' or anything.

Ballpoint pens do not work through gravity, rather they work through capillary action. If you hold a ballpoint pen upside down on Earth it will stop writing because the capillary action is insufficient against the force of gravity. In orbit there is no "upside down", no force of gravity to work against capillary action. In orbit, capillary action is sufficient.

And astronauts can do what we do on Earth, shake the pen.

Here is a repeat of Phillip's experiment but writing horizontally with the paper against the wall to negate the force of gravity. As you can see, but perhaps not read because of my handwriting, the pen works. I've used a Pilot G-2 gel ink ballpoint pen which retails for about $2 US.

Writing facing down

Just to demonstrate the pen works.

Writing against a wall

Writing with the paper flat against a wall to simulate 0 gravity. The pen continues to write because it works by capillary action. My handwriting remains as terrible as ever. More writing. Lorem ipsum etc. This is a pilot G-207. A good pen.

Writing upside down

The pen is having trouble now. And this is very awkward. It still works. (Ed: The ink is becoming faint in the last sentence.) A simple shake and it's back. A good pen will write upside down for a while. (Ed: Becoming faint again.) A shake brings it back.

Here we see Scott Kelly on STS-133 with what appears to be a space pen and a marker in his pocket, plus several mechanical pencils attached to the console.

And here is Cosmonaut Oleg Artemyev with the wide variety of writing implements used on the ISS.

Answer 2

EDIT: While I always believed this to be true, it looks like @Schwern has shown me otherwise! The link in their answer (which is the correct one) shows that ballpoint pens do indeed work in space.

(Also, I'm embarrassed to not have tried their simple extension to my experiment, by writing horizontally against a wall, which would have immediately shown me I was wrong.)

The more you know...

---

Ballpoint pens need gravity to push the ink onto the ball point that in turn transfers it to the paper when it rotates. As a result, they won't work in space. In fact, you don't need to go that far: they won't work when you're trying to write upside down, either!

I can't believe I never tried this before, but I just did a little experiment: I wrote a passage on paper, and then tried to write the same passage lying on my back in bed. You'll notice that there's still some ink on the point, so a couple of words do come out, but it stops very quickly. I then tried to write "normally" again, and you'll notice that it takes some time for the ink to flow back down to the point, but once it does, writing's back to normal again!

EDIT: My little experiment only shows that the capillary force is easily countered by gravity, not that ballpoint pens need gravity to work.

Answer 3

Yes, ball-point pens can be used in space. NASA even has a web page specifically about the Fisher Space Pen:

Fisher developed his space pen with no NASA funding. The company reportedly invested about \$1 million of its own funds in the effort then patented its product and cornered the market as a result.

Fisher offered the pens to NASA in 1965, but, because of the earlier controversy, the agency was hesitant in its approach. In 1967, after rigorous tests, NASA managers agreed to equip the Apollo astronauts with these pens. Media reports indicate that approximately 400 pens were purchased from Fisher at $6 per unit for Project Apollo.

The Soviet Union also purchased 100 of the Fisher pens, and 1,000 ink cartridges, in February 1969, for use on its Soyuz space flights. Previously, its cosmonauts had been using grease pencils to write in orbit.

Both American astronauts and Soviet/Russian cosmonauts have continued to use these pens.

The Apollo equipment stowage lists shows each mission launched with 3 Fisher ("data recording") pens, 3 felt-tipped markers, and 3 pencils. Each astronaut launched with one of each writing instrument in their spacesuit. The Apollo 11 manifest is included below:

Buzz Aldrin famously used a pen to fix a broken circuit breaker.

The Apollo astronauts often wrote notes directly on the spacecraft walls. Photographs and analysis of Apollo 11 "graffiti" is on this NASA webpage. Most of the writing appears to be in pencil, followed by felt-tipped marker. However, there is also the presence of pen writing:

This answer has a photograph with writing on a spacecraft in Russian, using pen.

Answer 4

In space? Certainly. Aboard a rotating space station or a spacecraft undergoing velocity change - or any other circumstances that provided a force that moved the ink "downward" onto the paper.

The more interesting question is whether a ballpoint pen would work in zero (net) gravity. As ink moves from the pen to the paper there will be a miniscule reduction in pressure at the ball which could theoretically cause the ink to feed in that direction, but other effects are likely to be greater. The short answer is that standard designs of ballpoint pen rely on gravity to feed the ink to the ball when writing.

Alternatively, the pen could be redesigned so the ink was subject to another force pushing it towards the ball. The Fisher Space Pen used gas pressure for this.