Such a probe might not survive all the way to another star, and even if it did, communications would be a major challenge. But some suggest that the first destination for an interstellar probe need not be a star. A journey into interstellar space might do just fine, providing a technology shakedown and an incremental step toward the stars, just as the suborbital Mercury flights of Alan Shepard and Gus Grissom were the first steps toward Neil Armstrong’s “giant leap” onto the moon. NASA’s Les Johnson thinks that missions to distances of 250 to 1,000 astronomical units (two to eight times Voyager 1’s current distance) could be ready for launch within a few decades.
For most interstellar mission planners, the ultimate goal is to send people blasting across the cosmos in big honkin’ spaceships. Few expect that to happen for at least a century, leaving scientists and engineers plenty of time to work out strategies. Meanwhile, others are already considering what may be the most important element of star travel: the people who will make that long—and presumably one-way—journey.
Sheryl Bishop, a social psychologist at the University of Texas Medical Branch, has studied mountain climbers, cavers, teams that have wintered over in Antarctica, and others to understand the motivations and behaviors of those who operate in extreme environments. In 2005, she even participated in a simulated Mars expedition in the Utah desert, spending two weeks with an all-woman crew.
That work brought her to the attention of Danish filmmaker Michael Madsen, who is producing a documentary titled Odyssey about how we might select the crew for a “worldship”—a miles-long craft that would carry hundreds or thousands on a generations-long star trek.
“The limitless expectations we have on Earth don’t apply” to such a journey, Bishop says. “Columbus didn’t have to worry about breathing—he wasn’t going to suffocate if something went wrong with the ship. With a worldship, you’re through with everybody on Earth, and everybody on Earth is through with you. So what kind of person is both willing to go and sane enough to select? They’d have no family ties, they wouldn’t miss the skies and seas. After a while you start thinking, ‘Oh my God—I’m defining a sociopath.’ ”
Such is the state of interstellar-flight planning, circa 2013—separating the committed from those who perhaps should be committed, the visionaries from the daydreamers, the difficult from the impossible. Even the experts can’t always tell the difference, so they keep studying, keep advocating, keep pushing toward the stars.
Damond Benningfield is a freelance science writer and audio producer in Austin, Texas.