This is just the latest in a long legacy of sniggering stories about sex in space that posits getting your extraterrestrial freak on might be dangerous or even (as this story asserts yet again) "life threatening." The occasion for this latest volley is the first round of cuts — from over 200,000 applicants to 1,058 aspirants — in the Mars One screening process, leading to the eventual selection of a crew of 6 to make a one-way trip to Mars, but the topic of off-Earth coitus is titillating enough to have spawned a whole book, not to mention all of the giggling press pieces that bubble to the surface periodically, inevitably ranging from cautionary debunking ("it's not gonna be as hawt as you think") to outright fearmongering.
I find it depressing, and I think it's a symptom of the broad sex-negativity that still binds our culture, notwithstanding the ostensible sexual revolution of the last 50 years.
The most important ways in which life beyond the surface of the Earth will differ are high radiation and different (generally lower) gravity forces. The former is clearly a challenge, and potentially life threatening... but it is in no sense specific to sexual activity. Sex in space is no more dangerous, based on radiation exposure alone, than any other aspect of life in space. As as for low gravity, well, it might pose some challenges in terms of actually making the sex occur — as this soberer-than-usual article by Alan Boyle points out — but there's no reason to think it will make the sex risky.
No, when headlines breathlessly proclaim that outer-space sex is potentially "life threatening," what they really mean is that there's good reason to worry that pregnancy, childbirth, and early child development might not work well in low gravity. And we currently have no idea how much gravity is required to ensure that human procreation is safe, nor any real way to reliably find out.
This is a serious challenge; perhaps the single biggest obstacle to large-scale, long-term human settlement of space... but it doesn't mean sex in space will kill you!
Thought we lived in enlightened times, when sexual pleasure had been decoupled from procreation? Yeah, maybe not so much. You'd think that people writing about human spaceflight would be forward-looking out-of-the-box thinkers, but apparently even to many of them, sex begins and ends at babymaking.
Personally, I suspect the positional/logistical hassles of zero gravity will prove easy to overcome for creatures with, you know, hands and arms to grasp with and brains to direct them (and if you doubt it, consider that astronauts train for zero gee underwater, and then Google "underwater porn"1). And on Mars, whose gravity is 1/3 that of Earth, my guess is that the lightness of being will prove the polar opposite of unbearable.
Despite this story, later debunked as a hoax, and despite the fact that one married couple has flown in space together, nobody has yet tried sexual intercourse in space, and claims that portions of a porn movie, The Uranus Experiment, Part 2, were filmed on an aircraft performing zero-gee parabolas (similar to NASA's "Vomit Comet") are hard to confirm, but my guess is that once Virgin Galactic or one of its competitors starts regular operations, it won't be long before some adventurous couple books a whole flight for just the two of them and po
ps outer space's cherry.
My prediction is that, at least for space tourists, if not for later generations of permanent settlers, whatever practical challenges low/zero gravity poses will be overcome by the sense of novelty and adventure.
Certainly it's not going to kill anyone.