Sex in Space

Robert A. Freitas Jr.

Sexology Today 48(April 1983):58-64


Author’s note: As far as I know, this article (which was authored and accepted for publication in October 1982) was one of the earliest discussions of zero-gravity sexual technique ever published in the nonfiction sex research literature. I’d be interested to learn of any earlier (or later) publications on this subject, and will be pleased to post references or links to them here.

Other articles on this subject that were published afterSex in Space” (1983) are listed at the end of this paper.


This article is rated PG – parental guidance suggested.

Note: This web version is derived from an earlier draft of the paper and may possibly differ in some substantial aspects from the final published paper.



Astronauts, and later ordinary people, all will have the chance to sample the delights of zero-gravity sex in orbit. But they may frequently need to consult a copy of the NASA Sutra...

The room spins deliriously around you. Floating nearby, beside, above and below you, a room full of warm, naked people bumping, thrashing and whirling delightfully in mid-air. Like a sophomore’s wet dream, you are adrift in a delicious sea of friendly faces, hands, breasts and legs. Through the tumbling mass of smooth flesh you catch glimpses of a familiar blue-white orb outside the window of your room.

It is Earth.

As futurist Arthur C. Clarke once speculated on the future of mankind in space: “Weightlessness will bring new forms of erotica. About time, too.”

Accommodations for sleep aboard America’s new space shuttle are not the greatest from a sexological point of view. There are three bunks aboard the orbiter, and for those who don’t want a bunk, sleeping bags are available. Bunks have draw-curtains and are fitted with restraining straps. Without these, a completely relaxed sleeper would drift up and away, floating on whatever air current happened to be moving. Sleeping bags are multilayered and can be hung on a frame against the crew compartment wall. When a shuttle astronaut is ready for sleep, he or she zips open the sleeping bag, puts in some blankets, slides in and zips up. With a body strap around the sleeping bag, and the zipper closed, the bag is comfortable and can’t float around. There are no problems with sleeping in zero-gravity space. There’s no up or down so astronauts and passengers can sleep in any position. Without gravity it makes no difference whether your head is pointed toward the floor, a wall, or the ceiling.

Hardly the most romantic setting, but then pioneers have always had it rough. The Soviets have orbited two female cosmonauts to date, and are reportedly planning the first birth in space. (On the most recent mission, Russian commander Anatolly Berezovoy greeted the visiting spacewoman Svetlana Savitskaya with a terrarium of flowers and the suggestion that she cook meals for all five cosmonauts aboard the Salyut 7 spacecraft. “Not a chance,” declared Savitskaya. “Housekeeping details are the responsibility of the host cosmonauts.”) NASA has several women astronauts in the shuttle program, one of whom is married to another shuttle astronaut. There is a good chance that the two will fly together in the next few years, at which time all of America will be holding its collective breath – will we score a new “space first” against the Russians?

The best place for sex in space is in space – in mid-air far from any surface. No matter how a couple gyrates, bumps or bounces, once their center of gravity is fixed it will stay put...

In spacecraft like the shuttle, astronauts seeking a little fun must reckon with increased oxygen usage and lack of privacy. Finding footholds will probably be no problem in such cramped quarters, and sleeping bags are adequate for the purpose as any outdoorsman will attest. To date the largest space station occupied by human beings has been the American Skylab, a comfortable but sterile cylindrical habitat 48 feet long and 22 feet in diameter, with the volume of a three-bedroom house. In the decades to come larger stations, and later self-contained cities in space, may be constructed and inhabited by thousands of colonists. Eventually tourism will grow and a hotelier cooperative will finance the Space Hilton, where guests from Earth can come for sightseeing, medical recuperation, and to sample the many delights of life in zero-gravity.


Getting It Up

Upon your arrival at the Space Hilton you want to make sure you give yourself several days to acclimatize. During the initial period of weightlessness, there is a profound loss of stamina and physical reserves. There is a kind of jet lag as the body tries to adjust to the new conditions. About half of all astronauts become spacesick for a few days after reaching orbit, some worse than others. Unfortunately there’s no foolproof way to predict who is most susceptible. Regular seasickness pills don’t seem to do much good.

And watch out for those martinis. When you agitate the shaker to mix the drink, air bubbles will remain trapped, unable to float to the surface in weightlessness. The Skylab astronauts had a similar problem with their onboard water supply, which was pressurized with air to get it to flow from its storage tank. This caused problems for them which would be even more embarrassing during a sexual romp. Groused William Pogue, pilot on the third Skylab mission: “I think farting about five hundred times a day is not a good way to go.”

At last the two of you retire to your stateroom. You turn the lights down low and gaze romantically at the gorgeous blue-green Earth hiding behind great whorls of white clouds. The time, the mood, the place, all are right. But wait!

The one place you don’t want to make love in space is in the sack! This is because the slightest movement against a rigid surface (such as a bed) imparts an upward impetus, and before you know it you’re bouncing off the ceiling, banging into furniture, and otherwise flying uncontrollably around the room. The only way to make it in bed is if at least one partner uses leverage straps, or both of you tether yourself to the bedposts (space bondage?), or you use an oversized sleeping bag which is itself tied down to a wall or other surface. But these are all too much work, and not much fun.

Couples making it in mid-room will spew particles of various fluids into the air which will stick to walls, viewports, TV screens, telephones, and even the participants themselves...

The best place to make it in space is in space – that is, in mid-air far from any surface. Once brought to a stop hanging in the middle of the room, which we shall call the Center Position, a couple cannot reach a wall so long as they stay together. No matter how they gyrate, bump or bounce, once their mutual center of gravity is fixed it will stay put. Even if they are drifting very slowly because of air drafts they should be okay – Skylab science pilot Edward Gibson once waited 20 minutes to drift to a new handhold after inadvertently losing his grip on an opposing wall.

So what’s the best way to achieve Center Position? There are two techniques, which may be termed ballast and impact. Using the ballast technique, the two grab hold of each other and push gently up from the floor. When they are close to Center Position, they heave a counterweight covered with sticky Velcro toward the ceiling, thus transferring their momentum to the ballast and stopping in mid-air. The ballast slaps the ceiling and sticks until retrieved.

In the impact method, which seems like more fun, the partners go to opposite walls and gently push off toward mid-room. When they meet halfway they grab each other, again neutralizing their opposite momenta and halting at Center Position. This will take some practice to get right, as the lighter member of the couple must propel her or himself slightly faster and aim must be reasonably accurate.

Of course, except for the most practiced experts, the couple will always wind up with some residual rotation. While on Earth this would quickly disturb the vestibular organs of balance in the inner ear, causing dizziness and nausea, in space people are virtually immune to rapid rotational sickness. The reason is that after a short time in weightlessness, body fluids redistribute themselves from the lower body to the upper torso, flooding the semicircular canals and effectively short-circuiting the sense of balance. Astronauts riding a rapidly spinning “barf chair” aboard Skylab were so unaffected by rotation that when they closed their eyes they had trouble telling if they were turning at all. Particularly adventurous couples may wish to enhance the rotation rate by grabbing hold as they pass each other and swinging around. The rate of rotation of each person can then be controlled independently by extending (to slow) or retracting (to speed up) the arms and legs.

If three people wish to reach Center Position, they must push off from points located 120 degrees apart around the room, four persons 90 degrees apart, and so on. More participants means greater difficulty in getting all the momenta to precisely cancel on impact, but also implies greater stability once Center Position is reached because more mass has greater inertia. Another interesting feature of three-dimensional orgies is that the participants, once stabilized, can try their hand(s) at “sexual architecture,” using their bodies to build geometric shapes such as spheres, cubes, pyramids and spirals. Kinetic forms may also be constructed such as “windmills” or “Ferris wheels,” with some bodies serving as foundations and others as rotating members or moving chains. The laws of physics tell us that angular momentum is always conserved, so the rotation of any one part of an architecture can readily be transmitted to any other part.


Steaming The Windows

There will be a few problems with zero-gee lovemaking, but most are comparatively minor and probably may be overcome by superior technique. First, the redistribution of body fluids causes extra blood to pool around the heart, creating the false sensation that the body contains too much liquid. This depresses the sense of thirst, which can lead to dehydration unless people force themselves to drink. Also, sweat flows more freely in the dried space station air, so lover may become further dehydrated if they keep at it for too long without a break.

Our astronauts aren’t talking, but zero-gravity could possibly cause a slight decrease in the size of the erect penis, due to the heart not working as hard or as fast and lower blood pressure...

This same fluid redistribution causes the legs to become quite thin and the torso and head somewhat larger after a few weeks. Our astronauts aren’t talking, but it’s possible that this effect slightly decreases the size of the erect penis, especially since the heart isn’t working as hard or as fast and blood pressure is down. Heightened body sensitivity also is likely. A medical experiment designed to test astronauts’ reflexes found that their nervous systems speeded up in weightlessness, probably due to the increased physical alertness required for zero-gee living.

Another problem is the lack of convection currents in zero-gravity. Flames in Skylab’s furnace smothered themselves in their own smoke, and during vigorous bicycle exercise by the astronauts body heat didn’t rise but lingered suffocatingly around the men. During lovemaking body-warmed moistened air will tend to hang close to the skin. This is something like the warm blanket of water that forms around you in a swimming pool when you don’t move around too much. So sex in space may be a much hotter, wetter affair than on Earth, where gravity helps drain liquids from bodies at work and sex generally takes place on soft, absorbent surfaces. Couples coupling in mid-room will spew particles of various fluids into the air which will stick to walls, viewports, TV screens, telephones, and even the participants themselves – the space equivalent of steaming up the windows.

One last potential problem is transmission of venereal disease, which in space may not be limited to sexual partners and toilet seats. Fluids, small hairs, and other particles from the infected regions could stick to walls or drift into the Space Hilton’s ventilation system. There is a time limit for microorganism survival, but the potential for epidemic remains high if space dwellings, like hospitals, are designed as closed, compact habitats.


Several Mornings After

There’s a new morning every 90 minutes in low Earth orbit. Time to wake up!

In darkness on Earth you can always tell which way is up. Not so in zero-gravity. If you fall asleep while not in bed you could be rotating or translating across the room and not know it, and bang into something in the middle of the night. Or you make wake up sleeping on the ceiling or glued to an air vent. Skylab astronauts frequently complained that loose objects such as pants, shirts and socks would flap around the room and tickle them in the face while they were trying to sleep.

Upon waking and hitting the lights you may literally not know where you are. Astronauts who found themselves oriented more than 30-50 degrees from normal when entering a room often could not recognize the place even though they had lived there for weeks. you may need to turn a bit to get your bearings. The pooling of fluids in your head will leave you with a pounding headache if you overindulged the night before, but at least space hangovers will not be accompanied by dizziness.

For years adventurous couples have eagerly sought membership in the Mile High Club, the legendary fraternity of high-altitude sex. The successful launching of the space shuttle raises erotic enterprise to new heights. Our astronauts, and later ordinary people, all will have the chance to sample the delights and frustrations of zero-gravity sex in orbit. Pioneers of three-dimensional lovemaking will frequently need to consult their dog-eared copy of the NASA Sutra, as virtually anyone should be able to achieve even the most startling contortions. And the Sex-in-Space Race is already on: who will be first to join the Hundred Mile High Club?


Robert A. Freitas Jr. holds B.S. degrees in physics and in psychology, and a Juris Doctor degree (concentration in space law and international law). His technical papers have been published in Icarus, Journal of the Astronautical Sciences, Proceedings of the International Joint Conference on Artificial Intelligence, and the Journal of the British Interplanetary Society, and has had numerous popular articles published in Omni, Astronomy, Mercury, The Humanist, Science Digest, and regularly in Analog. He is Director of Space Initiative, which publishes Lobbying for Space, the original space activists’ “bible,” and is in the process of incorporating the Xenology Research Institute as a nonprofit organization for the purpose of collecting, archiving, analyzing, organizing, and synthesizing existing knowledge and writings on the subject of extraterrestrial life. Dr. Freitas holds memberships in AAAS, Astronomical Society of the Pacific, World Future Society, National Space Institute, Planetary Society, Smithsonian, and life membership in the L5 Society, and is an Associate Fellow of the British Interplanetary Society.



Earliest nonfiction publications about sex in space include:


Isaac Asimov, “Sex in a Spaceship,” Sexology (January 1973). Reprinted in Science Past – Science Future, 1975.


G.I. Plakhuta-Plakutina, L.V. Serova, A.A. Dreval’, S.B. Tarabrin, “Effect of 22-day space flight factors on the state of the sex glands and reproductive capacity of rats,” Kosm. Biol. Aviakosm. Med. 10(September-October 1976):40-47. In Russian.


Robert A. Freitas Jr., “Sex in Space,” Sexology Today 48(April 1983):58-64.



Nonfiction articles published after “Sex in Space” (1983) include:


Yvonne Clearwater, “A Human Place in Outer Space,” Psychology Today (June 1985):34-43.

Mary Madison, “NASA ponders sexual activity for astronauts” Peninsula Times Tribune, 25 June 1985, pp. A1, A12.

Mike Capuzzo, “Sex in Space: Do you want your tax dollars to support this?” The Miami Herald, 9 July 1985, pp. 1C, 2C.


Ben Bova, “Sex in Zero G,” Omni 8(March 1986):29.

James E. Oberg, Alcestis R. Oberg, Pioneering Space: Living on the Next Frontier, McGraw-Hill, New York, 1986.


Neil McAleer, The OMNI Space Almanac: A Complete Guide to the Space Age, World Almanac, New York, 1987.


M.P. Warren, “Effects of space travel on reproduction,” Obstet. Gynecol. Surv. 44(February 1989):85-88.

L.V. Serova, “Effect of weightlessness on the reproductive system of mammals,” Kosm. Biol. Aviakosm. Med. 23(March-April 1989):11-16. In Russian.

R.J. Levin, “Effects of space travel on sexuality and the human reproductive system,” J. Br. Interplanet. Soc. 42(August 1989):378-382.

“Experiment 8 Postflight Summary NASA publication 14-307-1792” (internet hoax, originally posted to newsgroup on 28 November 1989) ..... here ..... here ..... here ..... here


P.A. Santy, R.T. Jennings, D. Craigie, “Reproduction in the space environment. Part I. Animal reproductive studies,” Obstet. Gynecol. Surv. 45(January 1990):1-6.

R.T. Jennings, P.A. Santy, “Reproduction in the space environment. Part II. Concerns for human reproduction,” Obstet. Gynecol. Surv. 45(January 1990):7-17.

W.J. Sapp, D.E. Philpott, C.S. Williams, K. Kato, J. Stevenson, M. Vasquez, L.V. Serova, “Effects of spaceflight on the spermatogonial population of rat seminiferous epithelium,” FASEB J. 4(January 1990):101-104.

G. Harry Stine, “The Alternate View: The Three Dolphin Club,” Analog 110(April 1990):106-108.

R. Tucker, “Childbearing in space. A theoretical perspective,” J. Obstet. Gynecol. Neonatal Nurs. 19(July-August 1990):344-349.


Lance Frazer, “Sex in Space: the science of extraterrestrial reproduction,” Ad Astra (December 1991):42-45.


J.A. Hadley, J.C. Hall, A. O’Brien, R. Ball, “Effects of a simulated microgravity model on cell structure and function in rat testis and epididymis,” J. Appl. Physiol. 72(February 1992):748-759.

W.J. Broad, “Recipe for love: a boy, a girl, a spacecraft,” The New York Times, 11 February 1992, pp. C1, C9.

Marcia Dunn, “Sex in Space,” Associated Press, 5 September 1992. Also

Elaine Lerner, “Harness for sex in space,” True News USA, November 1992.

Arthur C. Clarke, “Sex in Space,” Playboy (December 1992):105-106 et seq.

U. Engelmann, F. Krassnigg, W.B. Schill, “Sperm motility under conditions of weightlessness,” J. Androl. 13(September-October 1992):433-436.

John Sturgeon, “Sex in Space,” 1992.


Julian Watson, “Sex in Space Harness,” letter to the Institute, ~July 1993.


Kenichi Ijiri (principal investigator, SpaceMedaka experiment, STS-65), “The First Vertebrate Mating in Space – A Fish Story,” 1994. Textbook ..... Movie


K. Ijiri, “Fish mating experiment in space – what it aimed at and how it was prepared,” Biol. Sci. Space 9(March 1995):3-16.


Ken Jenks, “Sex in Space,” in Humans in Space, NASA/Space Biomedical Research Institute, 22 January 1996.

R. Sullivan, “The hazards of reproduction in space,” Acta Obstet. Gynecol. Scand. 75(April 1996):372-377.


K. Ijiri, “Explanations for a video version of the first vertebrate mating in space – a fish story,” Biol. Sci. Space 11(September 1997):153-167.

G. Harry Stine, Living in Space: A Handbook for Work & Exploration Beyond the Earth’s Atmosphere, M. Evans and Co., 1997.


F. Strollo, G. Riondino, B. Harris, G. Strollo, E. Casarosa, N. Mangrossa, C. Ferretti, M. Luisi, “The effect of microgravity on testicular androgen secretion,” Aviat. Space Environ. Med. 69(February 1998):133-136. Also

H.G. Stratmann, “Sex in Space: The Fantasy and the Reality,” Analog 118(February 1998):45-59.

Rochelle Kohen, “Professor says practice space sex,” The Diamondback, 16 November 1998.

R.J. Noonan, “A Philosophical Inquiry into the Role of Sexology in Space Life Sciences Research and Human Factors Considerations for Extended Spaceflight,” Ph.D. Thesis, 1998.


Y. Koryak, “The effects of long-term simulated microgravity on neuromuscular performance in men and women,” Eur. J. Appl. Physiol. Occup. Physiol. 79(January 1999):168-175.

E. Ranta, V. Kaitala, J. Lindstrom, “Sex in space: population dynamic consequences,” Proc. Roy. Soc. London, Ser. B, Biol. Sci. 266(1999):1155-1160.


Barbara Gallagher, “No Space Sex?” Scientific American 282(January 2000):22.

Pierre Kohler, La Derniere Mission [The Final Mission]: Mir, l’aventure humaine, Calmann-Levy, Paris, 23 February 2000 (apparently, a work of fiction)

Daniel Sorid and Frederic Castel, “Sex in Space Author Defends Book,”, 24 February 2000. (re Kohler book)

Jon Henley, “Astronauts test sex in space – but did the earth move?” The Guardian, 24 February 2000. (re Kohler book)

Sex in Space,”, 2 March 2000.

Daniel Sorid, “Meet Me In the Airlock...Will Sex In Space Fly?”, 13 March 2000.

Yuri Karash, “Sex in Space: From Russia...with Love,”, 16 March 2000.

Alexander Miles, “Mir: It’s Not Just About Sex,”, 1 April 2000.

Raymond J. Noonan, “Sexuality and Space: Theoretical Considerations for Extended Spaceflight,” Aerospace Medical Association Poster Presentation, 16 May 2000.

G.A. Landis, “An all-woman crew to Mars: a radical proposal,” Space Policy 16(16 July 2000):167-169.

Sex in space is tricky,” Ananova, 1 November 2000.

Michelle Delio, “Sex That’s Out of This World,” Wired, 4 November 2000.

Raymond J. Noonan, “Sex in Space: An Interdisciplinary Synthesis for Present and Future Studies,” paper presented at the 2000 Annual Meeting of the Society for the Scientific Study of Sexuality (SSSS), 12 November 2000.

Peter Pesavento, “From Aelita to the International Space Station: The Psychological and Social Effects of Isolation on Earth and in Space,” Quest: The History of Spaceflight Quarterly 8.2(2000):4-23.

Pregnancy in Space Seems Possible,” Reuters Health, 18 December 2000.

Learn about sexual activity in space,” ThinkQuest, 2000.


Ben Bova, “Science: Sex in Space,” Magazine of Fantasy and Science Fiction, February 2001.

Michael Cabbage, “Lust in Space: Study tells all,” Orlando Sentinel, 11 March 2001.

Raymond J. Noonan, “Outer Space,” in Robert T. Francoeur, Raymond J. Noonan, eds., International Encyclopedia of Sexuality (IES4), Volume 4, Continuum International Publishing Group, May 2001, pp. 413-432.

Chris Colin, “We have liftoff,”, 15 May 2001.

Sex in Space Forbidden, Says Russian Cosmonaut,” Interfax, 1 June 2001. Also

Mark Henderson, “Sex in space: thin blue line keeps crews in check,” The Times, 3 September 2001.

Astronauts Supplied with Pregnancy Test Kits,” The Times, UK, 4 September 2001.

T. Ikeuchi, S. Sasaki, H. Yamamoto, H. Tatsura, H. Kamiya, Y. Umemoto, H. Kubota, Y. Kubota, Y. Yanai, K. Kohri, “Effects for libido of male mice by change of gravity in parabolic flight,” Biol. Sci. Space 15(October 2001):298-299. In Japanese.

Raymond J. Noonan, “The 200 Mile High Club – Why won’t NASA admit that sex in space is already happening?” The Position, 4 November 2002.

Eric Lefcowitz, “Has Anyone Had Sex in Space?” Retrofuture Today, 2001.

Albert A. Harrison, “Chapter 11. Off Duty, Sex in Space,” Spacefaring: The Human Dimension, University of California Press, Los Angeles, CA, 2001.

“Sex in Space,” Go2SpaceNow, 28 October 2010;