A common story circulated on the internet and elsewhere goes something like this:
In the mid-1960s, NASA spend over $1.5 million to develop a pressurized pen which the astronauts could employ to write in weightless and low-atmosphere conditions. The Russian cosmonauts used a pencil.
In reality, the truth is not nearly as interesting. Initially, both the Americans and Soviets used pencils on their space flights. However, in capsules with 100% oxygen atmospheres*, wooden pencils were highly inflammable. Broken pieces of pencil lead (which are actually graphite) were also a hazard. They could easily float into an eye or nostril or other body cavity. Pencil lead could also short out electrical equipment and render it useless. In addition, when graphite is involved in an electrical short, it produces intense temperatures, which again is nothing you want in a confined cabin filled with 100% oxygen--or even normal levels of oxygen.
Fisher Pen Company used its own funds, not the government's, to develop a pressurized pen which would write in the adverse conditions of space, and Fisher patented it in 1965. It then offered the pen for sale to both NASA and the Soviets, and both entities became highly satisfied customers of the product. The pen, which has a shelf life of over 100 years, is still used today and is also available to the public in a variety of models, including refills which can be inserted into "normal" pens. Each refill is good for about 30.7 miles (49.4 kilometers) of writing, and since it does not depend on gravity for the ink to flow, can be used to write while held upside down.
*American space capsules initially used 100% oxygen levels in order to save weight, but NASA changed this policy after the Apollo 1 disaster in 1967.
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| By Cpg100 (Own work) [CC BY-SA 3.0 (http://creativecommons.org/licenses/by-sa/3.0) or GFDL (http://www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons |
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