Jan Davis and Mark Lee were married before they went to space aboard Endeavour during STS-47. Photo: NASA

Even if the logistical difficulties of space sex can be settled, there's still the problem that microgravity makes sex, well, significantly less sexy.Astronauts tend to sweat more in space, and decreased blood pressure could make it more difficult for males to hold up their end of the mission. As for the female side of things, the jury is still out on whether microgravity is a bane or a boon to boobs. While one astronaut trainer has confirmed that bras are in fact worn in space, this is usually during the intense exercise regimens that astronauts are submitted to. Beyond that, it's a matter of personal preference.The gravity on Mars—about one third that of Earth's—"is light enough to do what you want [and] heavy enough to make it interesting," wrote Arthur C. Clarke.
ISS sleeping quarters, where the magic allegedly doesn't happen. Image: NASA.
Orbital Insertions
The study made its rounds on the internet for several years, eventually prompting NASA to respond a decade later when French science writer Pierre Kohler cited it as fact in his book The Final Mission. The whole thing was obviously a hoax, said NASA, given that STS-75 didn't launch until 1996, seven years after the paper was released. Perhaps this is for the better, as the acts described in the document sound far more uncomfortable and awkward than pleasurable.Nevertheless, this problem was tackled by the late novelist Vanna Bonta, who developed the 2suit specifically for the purpose of helping astronauts perform the proverbial orbital insertions. When two people wearing the 2suit come together in microgravity, the suit allows them to effectively create one large sleeping bag, solving the problem of drifting apart so that they can focus on their cosmic kamasutra or whatever it is they're into.Researching sex in space "is simply not a priority—there are too many more pressing issues about health and function in space."
In Space, No One Can Hear You Cream
Screencap from Ron Garan's Reddit AMA
The Social Dynamics
Image: NASA
Understanding how sex impacts small-group dynamics in isolation is a crucial component to its successful integration as a variable into missions to space. When small crews are forced to spend months or years in close confinement, figuring out ways to tolerate one another's presence and cooperate can prove to be very taxing. Having two love birds along for a ride might only complicate things further."Even though [the astronauts] are living up there for months at a time, the relationship is not 'we're friends and roommates hanging out.'
NASA's Astronaut Code of Professional Responsibility
Research suggests that having married couples on long duration missions in space analog environments tends to temper sexual competition and provide an air of familiarity amongst crew members, which can be very beneficial in high-stress situations. And yet, throwing marital problems in the mix could also bring unintended consequences."When we leave low earth orbit and are leaving the Earth for many months at a time, I think whether the question [of bringing your spouse along] is valid and something we'll have to address," said Garan. "Now that brings other problems: not all relationships last. Imagine a breakup on a 3 year mission to Mars."Indeed, whether or not Davis and Lee, NASA's only married astronauts to have flown together, managed to consummate their marriage during their space honeymoon, they didn't manage to keep it together on Earth: they divorced in 1998.For those concerned with the future of space travel—and perhaps the future of the human race—the potentially perilous unknowns surrounding sex in space aren't reason to abstain; they're an argument for probing deeper."[Sex] is a part of the human experience and needs to be accounted for eventually," said Garan. "We need to look at life on our planet from a different perspective. It has a lot of facets to it. It's taking a long term or big picture view and realizing that our sphere of influence is a lot bigger than we think. We're just beginning to scratch the surface on how that could propel us into a more positive trajectory. The possibilities are enormous."Read and watch documentaries about humanity's encounter with outer space in Motherboard's Spaced Out series."Statistically there are quite a few astronauts who are married couples and I think it would be appropriate to have those couples on long missions."