Legend has it that NASA allegedly spent millions on a "space pen" while the USSR used a simple pencil. This widespread myth is far more interesting in its details. At the dawn of the space age, both American astronauts and Soviet cosmonauts actually used pencils. Even mechanical pencils were used in the Mercury and Vostok programs. However, the pencils proved unreliable. Slate dust and wood particles in zero gravity could damage electronics or enter the crew's lungs. This created a serious hazard. The famous AG-7 "space pen" was developed by private inventor Paul Fisher in 1965, investing $1 million of his own money. NASA purchased 400 of them in 1967 for $6 each. Later, the USSR also acquired 100 of these pens for its Soyuz program. This pen writes in temperatures from -50 to 160°C and even underwater. Both powers chose the same reliable solution.