Geoffery A. Landis, of NASA’s Glenn Research Center, predicts the first star trek aboard a laser-powered sail ship could begin within 50 years as new methods of space travel put interstellar flight within the grasp of our grandchildren.
“I think that ultimately we’re going to do it, it’s just a question of when and who,” Landis told SPACE.com. “Interstellar travel, actually colonizing space and terraforming a planet, this is the exploration that everybody seems to want to do.”
Traditional means of space travel are too slow to push humans out of the solar system. Instead, Landis envisions ships with vast sails, propelled by laser light to about 10 percent the speed of light. Such a craft could make the 4.3 light-year trip to Alpha Centauri, the nearest star system, in about 43 years, though slowing down would be a problem. Stopping could take up to 100 years.
Society on a ship
Making such a long trip possible would require the use of a multi-generational crew of men and women, along with all the supplies they would need as a society.
John H. Moore, a professor of anthropology at the University of Florida, believes that for long-term space missions that could last more than one generation, a group of about 180 crewmembers of mixed gender would allow for procreation of the species and maintain genetic diversity. The social structure of such a crew, however, would be much different than those aboard today’s Space Shuttle.
“We would have to leave aside the military-style organization of a crew and instead follow a social structure along familial lines,” Moore said in a telephone interview.
This type of organization mirrors those developed by small tribal groups on Earth, where elders and the basic bonds between parent and child contribute to a working society. Family ties, with the obvious seniority structure between parents, children and older and younger siblings, Moore said, can be used to “construct a division of labor to accomplish any kind of work, including the work required for space travel.”
Freeze sperm, leave the men behind
Sending humans out into deep space over a period of generations probably means a one-way trip for those aboard, researchers say, and would require the development of reliable power sources and closed-loop life support systems. Landis has even suggested sending out crews consisting only of women to save on weight, replacing men with frozen sperm to insure reproduction later down the line.
But the gulf between astronauts on the Space Shuttle and colonists aboard a laser-propelled space ship is a big one. The technological hurdles of building a laser large enough (on the order of a 100 meters wide) in space, and designing a stable sail — not to mention the spacecraft itself — are not small.
“The laws of physics are on our side, but it’s a hard question to answer: is the technology going to be there?” Landis said, adding that to date, only a handful of scientists are thinking about ideas for advanced space exploration.
Destiny and a swelling Sun
Some scientists think interstellar space travel is an inevitable course for humans. Ultimately, the Sun will reach the end of its life, swell to the size of a red giant and swallow up the Earth in the process. If humanity didn’t reach out to the stars, all of its proverbial eggs would be in one basket.
“The Earth itself is not entirely a safe place,” Landis said. “It would be a good thing for our survival if we lived on more than one planet.”
Other researchers say that the human instinct of expansion and exploration are enough to drive men and women out of the solar system, with additional incentives including Earth applications for star-faring technology and the potential of finding life.
New advancements in technology are still needed to put humans on interstellar transports, but how to get there seems apparent. Over the last few years, researchers have used lasers to push miniature sails and even small craft. And the idea has been around for decades.
“As far as getting to the stars, well I don’t think there’s any other technology that we understand the physics of enough to do it,” said Leik Myrabo, who directed laser sail research under the Interstellar Technology program of NASA’s Jet Propulsion Laboratory.
Myrabo’s team used lasers to push a small swatch of carbon mesh, sail material, on a pendulum using only the power of light. Over the course of the project, about one year, technology had advanced enough to produce superior sail materials.
Meanwhile, other scientists have not ruled out more fringe ideas of space travel. Since 1996, NASA’s Breakthrough Propulsion Physics Project – also run out of the Glenn Research Center – has looked into the possibility of faster-than-light methods of transportation, like that alluded to by Star Trek’s “warp drive.”
“It’s only speculation right now, but it’s a worthwhile goal to shoot for,” said Marc G. Millis, an aerospace engineer who managed the program through 2001. “I’m as willing to entertain the possibility that we can do it as I am to think we’ll learn a lot more valuable things by trying, than by not making the effort at all.”