Their bodies pressed together, the two lovers tremble in synchronicity. They cling like this for about half a minute, their extremities aflutter. Then they part. It's time enough. They have created new life in space.
Not from an X-rated sci-fi flick, the scene occurred in real life aboard a space shuttle in the summer of 1994 and made history of a sort. The romancers, small fresh-water fish from Japan known as Medaka, hold the distinction of being the first and only vertebrate creatures ever known to mate successfully in the weightlessness of space. There is a video of the event, not to mention space-born offspring, to prove it.
The public has long been fascinated with the free-flying romantic potential of weightlessness. And yet, the textbook on sex in space remains largely unwritten.
Advocates of human spaceflight in the United States and other nations have long known that, sooner or later, they would have to address the sensitive issue more directly. With the advent of the $63 billion, 120-ton international space station, some researchers hope, the excuses for evasion may soon fade away.
The arrival of the station's first residents, set for early November, heralds a new era in which people will learn to live and work in space for extended periods, its advocates say. The facility is designed to serve as a stepping stone to the solar system. But humanity's ability to spend years in transit across the void, or colonize other worlds, could ultimately depend on an ability to reproduce and raise healthy children, as well as plants and animals, in those environments. Much more than voyeurism will be at stake, then, in the pursuit of understanding spaceflight's effects on sex, reproduction and development in living organisms.
"There is nothing that suggests there would be any problem with humans mating" in microgravity, according to University of Texas obstetrician/gynecologist Richard Jennings, former chief of flight medicine at NASA's Johnson Space Center. Eventually, "issues of reproduction and development will be very important" not only in zero-gravity but in the varying gravities of the Moon and Mars.
As women have joined men in space in increasing numbers and for longer stays, rumors and speculation have swirled around the topic of that most intimate of orbital rendezvous. But for the foreseeable future, officials and researchers emphasize, critters other than humans will be the only ones testing their procreative proclivities in orbit. NASA has never sanctioned any experiments in which humans attempt sex and has no plans to do so. And astronauts reject as ludicrous any suggestion that they would indulge in zero-G hanky panky.
Scientists note that a number of babies have been born to men and women after they have flown in space, showing that the physiological processes can remain healthy postflight. Early in the space age, the Soviets found the question pressing enough that Valentina Tereshkova, plucked from a job at a textile factory to be catapulted into space in 1963, "came back, mated with a cosmonaut, and produced a healthy baby," according to a senior NASA biologist. "I'm told it was by design." The couple got married along the way, historians note, but soon separated.
Because of the elaborate physical monitoring that took place during the early days of manned space flight, in which sensors recorded the most intimate bodily functions of the astronauts, NASA sources say they can reliably report that male hydraulics will work in weightlessness. …