Sex may happen in space, scientists say.

"Sex and romantic entanglements among astronauts could derail missions to Mars and should therefore be studied by NASA, warns a top-level panel of US researchers."

- Maggie McKee for NewScientist.com

I guess you really can't dismiss human sexuality once you observe it in the vaccuum and outside Earth orbit. Kudos to NASA for staying skeptical so long: That's the way you do science.

Meanwhile, anybody really curious about this phenomenon might want to look back at the model studies, which are highly suggestive:

"In an 8-month space station simulation on Earth in 2000, a Russian man twice tried to kiss a Canadian woman researcher just after two other Russians had gotten into a bloody brawl. As a result, locks were installed between the Russian and international crews' compartments."( Ibid )

I think it's pretty clear we're looking at a significant effect here and space engineers are quite right to begin taking it into account. Then again, maybe NASA should just stick to robots.