It's now official: there is no truth to the rumor that space travelers engage in sex. "We do not have such experiments in our country," said Valery Bogomolov, deputy head of the Institute of Bio-Medial Problems, commenting on a widely circulated document on the internet about an alleged 1996 sex experiment made by NASA on 10 sexual positions.

"There is no proof... that on any mission cosmonauts had sex," he told a news conference in Moscow on Wednesday, Interfax reported. "Cosmonauts, too, are regular people, but... I have not heard about any sex in orbit."

The scientist also referred to an experiment conducted by the institute, which researches space health issues by simulating flight conditions on a mission to Mars. Six cosmonauts, including a woman, spent two weeks isolated in a zero-gravity capsule, but "there were no complaints over the absence of sex," Bogomolov said.

The question of sex in space was first raised when a woman joined three cosmonauts aboard a cramped Soyuz rocket in 1982. In 1991, U.S. astronauts Jan Davis and Mark Lee married before their joint space orbit; fueling further rumors of sex in space.