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.