The debate about human spaceflight shouldn’t be about destinations like near Earth objects, but instead about developing capabilities and modern rationales for traveling beyond Earth orbit. (credit: DigitalSpace)

Making the path for human spaceflight less rocky

by Dan Lester
Monday, June 21, 2010

The new direction for US taxpayer-funded human spaceflight, and the dismantling of an earlier architecture to do it that was termed non-executable, has led to painful cries about lack of destinations and some exasperation about looking without touching. To the extent that destinations should be rocks with perhaps at least a little gravity, and to the extent that touching involves wriggling toes in the dirt, those cries are perhaps justifiable. But to the extent that advancement of human spaceflight is really just about humans being able to travel beyond our home planet, such cries are hollow. It’s that ambiguity that prompts some discourse.

The Augustine Committee concluded unanimously that what human spaceflight should be about is the ability to leave the Earth. In their words, “chart a path for human expansion into the solar system.” While the committee concluded that human spaceflight nurtured technology development and conveyed both inspiration and a spirit of leadership, a subtext was that populating the cosmos could be important for both economic gain and for preservation of the species; in the former case to make some money, and in the latter case as insurance against bad things happening. While our nation has not conspicuously bought into either of these goals with regard to taxpayer-funded efforts, the second is particularly enabled by human spaceflight.

For science, it’s increasingly difficult to demean the capabilities of robotic or, more precisely, telerobotic craft. Our capabilities here increase on a steep trajectory, as per Moore’s Law and increasing communication bandwidth, while that of astronauts don’t. Sure, we’d all like to have a human geologist picking up rocks on the surface of Mars, brushing them with a fingertip, and squinting at them through a helmet visor. But for the same cost we could spread telerobotic craft across the surface of the planet, inspecting rocks with higher observational facility than the human eye can provide. This all under the direction of humans who just happen not to be there physically. For a geologist who could do in a day what a robot could do in a month, a few dozen robots working 24/7 would be stiff competition. Even for on-orbit servicing and construction of spacecraft—a profoundly enabling capability at least for science—the unique advantage of in-situ human hands isn’t entirely clear. While human spaceflight can certainly contribute to science, that isn’t its main value. This has largely been conceded in the last decade of human spaceflight planning.

For mining resources in the cosmos, on-site humans are only arguably necessary. The value of such a human to an open pit mine and refinery, at least in its early stages, is akin to kicking the scoop when it gets stuck. But the cost of providing that kick with a human foot is enormous. One can envision teleoperated and even autonomous systems that are engineered to be resilient with respect to such problems. These would be much cheaper than an on-site human being even if they needed to be replaced. For the Moon at least, control latency is minimal, and virtual presence is nearly immediate. Bringing the solar system into our economic sphere is a great idea, but it doesn’t clearly need spacesuited humans driving bulldozers and holding shovels.

All that being said, bad things do happen, and our species has some obligation to preserve itself. Charting a path for human expansion into the solar system by at least representatives of our species is insurance against the many bad things that could make the Earth less habitable. That’s simply not a job that telerobotics or virtual presence can satisfy.

In these respects, our new plan for human spaceflight is noteworthy. With an emphasis on propulsion, propellant storage, closed loop life support, and radiation protection, it’s not about landing on this rock or that one. It’s about creating a path and, more specifically, it’s about leaving. Leaving may well involve landing on a rock, and wriggling ones toes in the dirt, but that’s not a necessary condition. Such regolith worship involving flags (perhaps, more specifically, flagpoles), and footprints that can be impressed in it is not a primary need. Nor, in the near term at least, are resources that could in principle be extracted from that regolith.

It should be understood that species preservation can’t be considered to be a unilateral task. One might suspect that this is why the Augustine Committee didn’t highlight it. The US taxpayer has no responsibility to protect the species as a whole, though perhaps has some incentive to protect themselves and their own way of life. In that respect, human spaceflight could be considered a tool for national security. Even for that, humans aren’t programmed to protect themselves from something by leaving. That’s not a culturally attractive option. Our instinct is to stay and fight. But in the case of planetary catastrophe, it’s the ability to leave—at least to reposition, if not escape—that actually conveys what has been termed soft power.

The word “exploration” is often used to describe our motivations for human spaceflight. It’s a term that echoes through all discussions of space endeavors. But that word, which reflexively connotes images of Columbus on the one hand, and Lewis and Clark on the other, has been rendered somewhat obsolete by modern technology. It’s no longer really about sending people to go out and discover things. That can be done better in other ways. Rather, it more resembles making it possible for people to leave, blazing the trail for us to do so if we really need to.

So how do we get taxpayers to buy into that grand goal of being able to leave, which is a truly unarguable and completely unique justification for human spaceflight? It’s not a matter of just telling NASA to do it. The Space Act that defines the agency says nothing about species preservation, and actually doesn’t even say anything about human spaceflight! One might suppose action on that goal would be spurred by a clear threat to humanity. Recognition of large numbers of NEOs and the paleontological and geological history of their previous impacts could be interpreted as presenting such a threat. That particular threat doesn’t appear to be imminent, but of course neither is our ability to leave. Some would say that an obvious way to deal with that particular threat is by visiting a NEO, though the value of such a human visit in the name of species protection is far from self-evident. A more compelling human spaceflight response is learning how to leave.

Buying into that goal is something that will require getting over a dated perception of “space exploration”, which the public can’t quite seem to digest. Survival of the species is clearly a multilateral responsibility, so international partnership has to be part of the mix. It will also require that we get over the idea that “rocks as destinations” is what it has to be all about. There are only so many rocks, and few significantly-sized ones that are even remotely convenient to visit, the Moon certainly being one. Lots of them are pretty small! How big does a rock have to be to constitute a target for “exploration”? Going to rocks is a good thing in the greater endeavor of expansion, but if our progress in human spaceflight is measured by visits to rocks, it will be frustratingly slow.

That being said, “But where do we go?” is probably a faulty question, especially if the answer has to be a rock. The right question is, “How can we go?”, at least in response to what can be considered the precariousness of our species in a cosmic context. Answering that question will give us both power and pride.

Dan Lester is an astronomer at the University of Texas. He is active in NASA strategic planning activities, writes regularly on space science policy, and occasionally even dares to challenge reconciliation of space exploration with national needs.

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