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By 20th century expectations, we are way behind schedule on colonizing the solar system. After the Apollo moon landings, some scientists and NASA officials envisioned launching astronauts to Mars in the 1980s and building cities in space to be habitable by the 2000s. But the only humans in space today are a few astronauts in a lone space station orbiting Earth.
That may soon change, says science writer Christopher Wanjek. China is preparing to send crewed missions to the moon by the 2030s. SpaceX founder Elon Musk hopes to take people to the Red Planet, while Bigelow Aerospace is drawing up plans for Earth-orbiting hotels. Increasing competition for the geopolitical power and profits promised by space travel (SN: 12/21/19 & 1/4/20, p. 31) may finally get astronauts back to the moon and beyond, Wanjek says. In Spacefarers, he explores how this 21st century space race could play out.
Drawing on the science and history of space exploration, Wanjek paints scenes of future human activity across the solar system. “A two-week trip to the moon [would] be much like an African safari was 150 years ago,” he writes. “Initially for the wealthy, with a tinge of danger, and certainly not for the kids, at least not at first.” On Mars, too far for a weekend getaway, self-sufficient colonies could serve as a pit stop between Earth and minable asteroids and as the frontier of the outer solar system. Wanjek expects a permanent human presence on Mars in the 2050s and visits to Jupiter’s moons by 2100.
Wanjek tempers these far-out ideas with frank discussions about the perils of space travel. There are oft-cited worries, like the fact that, as Wanjek puts it, “living in microgravity sucks.” Weightlessness weakens bone and muscle, and Wanjek is not convinced that the International Space Station diet and exercise regimen is enough to keep astronauts fit for the long haul to another planet. Then there are less obvious concerns, like how a Mars colony growing light-sensitive crops underground is supposed to restock LED bulbs.
Experiments in the 1990s provide a humbling illustration of how space missions could go awry. Inside a prototype Mars colony dubbed Biosphere 2 in Arizona, bugs multiplied, crops failed and crew members split into factions. After the disaster that was the first two-year mission, a second attempt in 1994 lasted just six months before dissolving into “vandalism, foul language, lawsuits, finger-pointing, shaming,” Wanjek writes. “You know, typical Mars colonization kind of stuff.”
Despite spending much of Spacefarers poking holes in space travel schemes, Wanjek is optimistic that humans will eventually need to specify a solar system body on postal addresses. “You can’t launch humans to Mars on a tank of hope,” he writes, but humans have never been closer to embarking on a voyage beyond the moon.