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Writing in Space with a Cheap Ballpoint Pen
Roland Piquepaille writes "Some days bring big surprises. Like many people, I always believed that it was impossible to write in space with ordinary pens because ink would not flow. So imagine my astonishment when I read Pedro Duque's diary from space this morning. Pedro Duque is an astronaut since 1992. Now, he's on board of the International Space Station (ISS) since October 18, 2003. And he's writing -- from space -- with a cheap ballpoint pen, like Russians apparently always did: 'So 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.' Isn't it amazing? This summary contains more details and a photograph of Pedro Duque on board ISS." Note that NASA didn't go crazy developing a pen for space. Surface tension is the important factor for all pens, not gravity.
The ink cartridges in some pens is pressurized.
I think lack of gravity matters. In your upside down pen, gravity will pull the ink away from the ball.
It's the surface tension propteries of the ink, commonly known as capillary action.
We must be alert to the danger that public policy could become captive to a scientific-technological elite. - Eisenhower
because they have multiple purposes. Imagine an electronic wire broke within the ISS: Using a pencil one can at least use the conducing graphite to link the two parts together again. I don't see you do this with a cheap (plastic) BIC-pen :=)
:)
Ofcourse, one can also break a pencil in two, and voila: TWO pencils, you colleague astronaut has one too now...
Third option, that a pen doesn't normally provide, is the fact that a pencil can be erased more easily without nasty chemicals. Easy if you want to wipe out the last log-entry in which you were a little drunk and have written down nasty things about the flight-captain.
When you need to draw a very fine line, one can sharpen the pencil to make it so. I don't see them sharpening a pen
Concluding: regardless of the truth of the "pen doesn't work in space but pencil does" story, it is still a much more versatile tool than a pen, so it "works" better....
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I guess in 1965-67 business and business leaders still had some integrety.
Fisher just developed the pens to be helpfull.
Of course having NASA use his pens was great advertising and did give them a great run in the comercial sector.
Problem with a pencil is the graphite dust. Normal gravity, graphite dust isn't an issue, it gets mostly on the paper, you don't worry about that. Now, in space, that graphite dust lingers, gets into things, makes the environment not as friendly to be in as it could be. With a pen, this is much less of an issue, as the physics of writing are a lot different.
Marxism is the opiate of dumbasses
The reason for using pressure in pens, it seems, is that surface tension alone may not be enough to pull a long column of ink through a narrow tube. If there is a little bubble in the column of ink, the surface tension is broken, and there is no way to pull ink past the bubble.
The problem of a bubble in the column of ink happens on land, too, not just in space. People deal with it by just throwing the pen away. Since cheap pens cost less than 15 cents, someone may develop the habit of throwing away pens without noticing what he is doing. If a bubble develops, it is usually after the pen has had considerable use, so there is little complaint.
In situations of varying temperature and outside air pressure, unpressurized pens may develop a bubble more easily. Pressurized ink cartridges are a little more reliable, and cost the manufacturer only a little more.
Because gravity is still in action on the ink when the pen is horizontal, at a guess. Writing with the pen held horizontally isn't the same as writing in microgravity - in microgravity the stickiness of the ink is more than capable of pulling more ink towards the ball as it writes, whereas with the pen held horizontally in normal G it still has to pull ink "uphill" against gravity towards the top of the ball.
It'a another example of how nearly impossible it is to extrapolate what happens in space or on the Moon from our experiences on Earth - for more examples, check out Bad Astronomy on the Apollo "Hoax"
http://www.snopes.com/business/genius/spacepen.asp /
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Now according to the Snopes article, the main problem was tips breaking off pencils and floating around. Graphite dust would not have been a problem, because I believe they were using lead pencils.
(Granted, it would be an issue today if pencils are used in space, but in those days, it wasn't.)
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Pet Peeve: Perscription drug advertising to the general public.
You can buy pens that get around this problem. The Cross Ion is a good example; in the ink cartridge (non-pressurized), above the ink, there is what appears to be a clear gel that prevents the ink from moving. As the ink in the cartridge (The ballpoint is part of the cartridge) is used up, the gel travels down the barrel with the ink.
:p
The pen works perfectly well upside down, I've tried. Probably doesn't cost as much as a pressurized pen either
Um the graphite is already "frozen" because it is in its solid state.
Its not liquid or gas is it?
This has been tested using a candle on (I believe) one of the first Shuttle missions in the early '80s. Essentially, the flame is a sphere, instead of the traditional oval-ish shape. As long as a slight air current is present (which is on a shuttle due to the ventilation system, and movement in general), the flame will remain lit. If the candle is placed in a sealed container, it will consume the oxygen in the immediate vicinity of the flame, then extinguish. Interestingly, if oxygen is reintroduced to the vicinity of the wick in a short period of time, the flame will reignite. The lack of air current prevents the wick from cooling below the point necessary to sustain combustion as quickly as it would in a traditional environment.
Children in the backseats don't cause accidents. Accidents in the back seats cause children.
A ball of fire that lasts until it uses up all available oxygen?
Yup. That's about right.