Packing for Mars: The Curious Science of Life in the Void

Roach interviews volunteers at the Flight Analogs Research Unit (FARU) at the University of Texas, part of a NASA bed-rest study in which participants spent three months in bed to simulate gravity’s degrading effects on bone and muscle mass. Dubbed “terranauts” (214), the volunteers were a mix of individuals: Some had joined the trial for the money ($17,000 total), others for the sake of science.

Gravity deteriorates bone mass; preventive measures, such as exercising, are difficult to perform in zero gravity. The weakening of bones is a significant problem for a Mars mission: A two-year mission could reduce bone mass by as much as half. For astronauts who returned to Earth after a long period, bone regrowth proved slow and partial, leaving the hip bone vulnerable to fractures. Roach is surprised to learn about a study that attempted to stimulate hip bone growth by purposefully and repeatedly having test subjects fall on their sides.

Research on bears also intrigues Roach: These animals redistribute calcium from their blood and do not lose bone mass after months of hibernation. Roach mentions the popularity of hibernation chambers in science fiction, and asks scientist John Charles whether NASA intends on developing such technology. Charles acknowledges space agencies’ fascination with cryosleep, but does not regard it as an efficient option. The chambers could malfunction, and the savings of packing fewer supplies wouldn’t balance out the risks and costs of developing the technology. Roach is also skeptical that consuming the necessary stores of fat would be healthy for humans.

Sex in space is just as implausible as it is impossible. The closest references to sex Roach finds in NASA and ISS documents are code of conduct statements that disapprove of inappropriate behavior or preferential treatment. Without much data to analyze, Roach spends a portion of the chapter debunking several hoaxes. A pornographic film claimed to have shot a sex scene in zero gravity, but after watching all three movies in the series, Roach discovers that the actors feigned weightlessness. She also disproves claims of dolphin threesomes (a third dolphin does not help with the pushing) and NASA experiments with underwater copulation, which never took place.

Though Roach finds very little information on whether sexual intercourse has ever occurred in space, she does discover some research on fertility and reproduction. She learns that the human penis does not benefit from an extra blood flow in zero gravity, but bull sperm move faster in space. One study sent pregnant rats into space. When they returned and gave birth, uterine contractions were weaker after the flight and reduced the stimulation of necessary stress hormones. Dr. April Ronca, the scientist who conducted the rat study, admits that little is known about reproduction in space partly because of lack of interest and funding. Roach points out in a footnote and in the chapter’s conclusion that institutional sexism plays a role in the lack of research on obstetrics and space.