As we continue to flounder along without a strategic direction for space, there are developments to note. The closing date for the submittal of white papers to the National Academies Study on Human Spaceflight has come and gone. Just under 200 submittals are available for viewing on the NAS study web site. As one might expect, they run the gamut from well-reasoned and carefully articulated essays to a few “creative” suggestions apparently submitted in large part for their amusement value.
I didn’t do a statistical study but the bulk of the serious submissions seem to have two distinct themes running through them. First, setting goals – and in particular, goals of destination – is seen as important. The idea that we should poke along “developing technology” and then decide to go somewhere at a later date does not find strong support in most of the papers. Second, there are two camps in regard to a national level of effort, the larger one claiming that the civil space budget should be increased to a level commensurate with those specific writers’ proposed goals and a minority view suggesting that understanding what you are trying to accomplish is more important than the amount of money spent. I find myself in the latter category.
Interestingly, these themes are also evident in the current drama playing out in the House Space Subcommittee over the new authorization bill for NASA. The Republican majority released their draft authorization three weeks ago to howls of protest. It features a sizeable cut in NASA’s budget from the administration’s request (in line with the current sequestration numbers) but is most notable for requiring a return to the Moon and for discarding the proposed “haul asteroid” mission. An alternative bill produced by the minority augments that funding $1.235 billion, makes a human Mars mission the main goal (within 15 years, no less) and leaves the Moon/asteroid choice to “technical experts at NASA.” Given that the GOP controls the House, the final authorization will likely look more like the majority version than its alternative. How this will be reconciled (or not) with the yet-to-be-revealed Senate authorization remains to be seen. Most likely, there will be no reconciliation and no new authorization – another continuing resolution for NASA is probable.
So in Congress, just as in the submitted NAS white papers, we see a corresponding set of conflicting visions – which goals to pursue and how much money to spend. Interestingly, neither side of the House subcommittee seems enamored with the haul asteroid mission. This development comes just as the agency begins its full court press to “sell” the concept to Congress and to the public. Most notably, NASA Administrator Charles Bolden wrote an editorial in The Hill, declaring the supposed benefits of the asteroid mission. He claims three: 1) conduct a “deep space” mission to give the agency experience in these operations; 2) allow the astronauts to practice “potential resource utilization” of the asteroid; and 3) “inform future efforts” at asteroid interdiction, i.e., to deflect a hypothetical Earth-crossing impactor from colliding with us at some distant date. Are any of these alleged benefits real?
Certainly experience with people in “deep space” operations (in this case, beyond low Earth orbit) is desirable. But such experience is also gained by return to the Moon, voyages to the L-points, NEO rendezvous, or missions to the martian moons, none of which require an asteroid to be procured as a target beforehand. As for “resource utilization,” I applaud the agency’s newly found interest in this topic, having argued myself repeatedly for its importance in creating new space faring capabilities. However, as a target for resource utilization, a captured 3-meter asteroid placed in lunar orbit is not a rich source of anything in particular. Volatile-rich asteroids are known to exist, but are not common and it is not clear than a small object of appropriate composition exists in a suitable orbit for capture.
Even if one is found, asteroid water is not like lunar polar ice. Water in these primitive asteroids is found in a chemically bound form (in clay minerals) and is not easily extracted. The clays must be identified, separated and processed to break the chemical bonds that hold the water molecules in their mineral structures. Such processing isn’t fully understood conceptually and will likely be difficult to accomplish in microgravity (typical industrial chemical processing requires thermal convection and density separation, both dependent on the presence of gravity). Moreover, the Orion spacecraft is neither a good platform for such experimentation (lacking adequate laboratory facilities and sufficient electrical power) nor can it loiter proximate to the asteroid for extended periods of time. At best, a few rock samples might be collected for return to Earth for later analysis and experimentation on resource processing. Oh, by the way, we can get a head start on that work right now – we already have several hundred pounds of meteorites of suitable composition in collections right here on Earth.
The last rationale for this mission, as Bolden describes it, is to help us prepare for future asteroid collision interdiction. One wonders exactly how this mission contributes to that goal. Certainly the act of moving an asteroid is relevant to deflection efforts – but we already know that a force applied to a mass in space will accelerate it (Newton’s law), so there really isn’t any question about the basic physics. There are issues with the physical structure of asteroids, with a porous, incoherent rubble pile being more difficult to manage than a solid, dense rock. But we don’t need to retrieve an asteroid to make this determination. In any event, an Earth-threatening object would be much larger (multiple kilometers) than the asteroid brought back in this effort (a few meters), so the technique of “bagging it and moving it with solar electric thrusters” is not really relevant to the problem of asteroid interdiction. So how will this “haul asteroid” mission help us protect the Earth?
The whole subject of planetary defense has a somewhat nebulous rationale. Despite the recent bolide collision in Russia, which spawned a number of quasi-hysterical press reports, the risk of a life-altering asteroid collision is actually quite low. Check out this diagram from The Economist – your risk of being killed by an asteroid impact is roughly 1 in 75 million. For comparison, your risk of being struck by lightning is about 1 in 500,000, of being attacked by a shark is 1 in 11 million, and being killed in a terrorist attack is about 1 in 20 million. You are actually more likely to die in an asteroid impact than you are to win the Powerball lottery (1 in 175 million). Is it logical or prudent to make asteroid defense an integral part of NASA’s mission, given that its likelihood is of such low probability?
One could argue that focusing on terrestrial volcanism is more appropriate, as the chance of a supervolcano eruption of Yellowstone (which would definitely change the global climate pattern) is about 1 in 730,000, or roughly 100 times more likely than an asteroid impact. But that’s relative to another extremely unlikely event.
Bolden’s attempt to justify the haul asteroid mission is unconvincing. On inspection, none of his supposed benefits are either attainable or (in fact) benefits. This mission concept merely poses as a space accomplishment. It masks the basic fact that we are an Earth-bound species and given this mindset, are likely to remain so indefinitely. There is no sense of creating a permanent, enabling space infrastructure that permits us to imagine and accomplish many different and varied types of missions. Instead, we continue to fantasize about future “space first” stunts, rather than actually doing what is possible and useful. Some would dream indefinitely about cities on Mars rather than actually realizing a true permanent transportation system in cislunar space. The dream of the impossible trumps the building of the achievable. No wonder we have a floundering and dysfunctional space program.
We constantly hear the lament that the American people have lost interest in space and have stopped dreaming about going into space. Perhaps some people have grown tired of waiting decade upon decade for their space agency and elected officials to devise and fund a realistic program that moves from dreaming to doing – from flags and footprints to building a permanent infrastructure – a program that actually moves outward, one that the American people recognize will finally include them.
Previous posts on impacts, asteroid missions and space resources: