Beyond the Moon
It’s not a place, exactly. But it could be NASA’s next destination.
- By Guy Gugliotta
- Air & Space magazine, April 2013
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Long an advocate of harvesting lunar water to fuel a transportation system in the Earth-moon neighborhood, Spudis regards NASA’s failure to emphasize that goal as evidence of the agency’s shortsightedness: “If you want to build a space system, you have to learn how to extract resources from the moon,” he says. “There is water ice on the moon and it can be accessed, but the [L2] mission is not long-term. It is configured as a place for Orion to go, not as a place to build a capability.”
Hopkins agrees that L2 is a short-term mission, but doesn’t see that as a negative. “We don’t envision a long-term commitment to infrastructure at L2,” he told the NRC panel. “We would envision a series of missions to do a few things, then move on to the next destination.”
As to whether any of this will actually happen, NASA can’t be sure. In January, when a reporter asked Gerstenmaier where he’d like to send Orion after its initial tests, he smiled and answered like a diplomat: “In terms of my own personal preference, I really don’t have one…. I try to lay out the data and let them [Washington officials] decide.”
All he can say for sure is that next year, a Delta 4 rocket is slated to fire an unmanned Orion 3,600 miles into space, then after two orbits bring it back at 20,000 mph to see if its heat shield can endure 4,000-degree Fahrenheit reentry temperatures. A second unmanned launch of Orion, aboard the Space Launch System, is planned for 2017, and a crewed mission is scheduled for four years after that. Gerstenmaier says the 2021 flight will travel to “the vicinity of the moon,” which includes several possibilities: going into lunar orbit, traveling straight to L2 and returning, or going to L2 and perhaps sliding to L1, on the near side of the moon. (Travel between Lagrange points is easy, requiring little more than a nudge in the right direction.)
Meanwhile, the planners keep planning. Maybe the most dramatic use of an L2 outpost is one proposed by the Keck Institute for Space Studies in cooperation with NASA’s Jet Propulsion Laboratory in California. They describe a mission in which a robotic spacecraft chases down a schoolbus-size asteroid, captures it, and brings it to the vicinity of the moon. There, astronauts could practice spacewalking around a small asteroid, extract water to make rocket fuel, and take inventory of its minerals.
The notion of capturing and relocating a half-million-pound asteroid began “as one of those ideas that when you first tell somebody about it, they look at you with glazed eyes,” says Louis Friedman, executive director emeritus of The Planetary Society and a co-leader of the study. “Then you get into it, and all of a sudden it becomes obvious to people that this is the only way to get astronauts to an asteroid in the 2020s.” Friedman says NASA has taken a serious interest in the proposal, and the agency said in a statement that it is examining the plan “to determine its feasibility.”
“The gut feeling is that we like L2, but it turns out that if an object is at L2 and let go, it will be unstable and could drift away” and possibly crash to Earth, Friedman says—although an object as small as this 23-foot-wide asteroid would burn up in the atmosphere. One problem is finding the right asteroid, he says. There are “millions out there,” but NASA and its international partners would need to set up a dedicated program to shop for candidates of the right size and type. The robot spacecraft would approach the asteroid, match its tumbling motion, and use a soft, inflatable bag in the spacecraft’s nose to grab it. Then the spacecraft would “de-spin” the asteroid and bring it near the moon. The entire capture mission would take anywhere between five and a half and 10 years, depending on the asteroid’s initial orbit and its mass.
As of early this year, NASA has not committed to an L2 mission. “The Lagrange points are very intriguing to us,” Gerstenmaier says, but adds that Gateway might turn out to be more challenging than it seems. “We need to know if there are too many unknowns. Am I not pushing hard enough? Or am I pushing too hard?” The most likely message to NASA from space enthusiasts? Push.
Guy Gugliotta, a former science reporter for the Washington Post, is the author of Freedom’s Cap: The United States Capitol and the Coming of the Civil War (Hill and Wang, 2012).