Quote Originally Posted by bisolvon View Post
When NASA first started sending up astronauts, they quickly discovered that ballpoint pens would not work in zero gravity. To combat the problem, NASA scientists spent a decade and $12 billion to develop a pen that writes in zero gravity, upside down, underwater, on almost any surface including glass and at temperatures ranging from below freezing to 300°C.

The Russians used a pencil.

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The reason they are not using pencils is that when the pointed tip broke it may fly freely to space and may affect the space gears used by the astronauts