Ideas can come from anywhere and sometimes institutions are created with the express purpose of generating ideas from which advanced technologies, products or capabilities may eventuate. These “think-tanks” have occupied a prominent place in American history since World War II, a time when science and technology emerged as a critical part of our national intellectual infrastructure. A remarkable series of concepts were developed out of such efforts, including the transistor (Bell Labs), game theory (Rand Corp.), and the Internet (ARPA). Less well remembered are ideas that for various reasons didn’t pan out, such as the Picturephone (Bell Labs) and atomic bomb-powered spaceships (Los Alamos National Laboratory and the Institute for Advanced Studies).
The W.M. Keck Foundation privately funds the Keck Institute for Space Studies (KISS). Located on the campus of the California Institute of Technology, KISS conducts “think and do studies” whose aim is to generate advanced concepts for space missions in order to revolutionize our approach to and the implementation of spaceflight. They hold workshops on a variety of study efforts, ranging from sweeping strategies for space exploration to the outline of specific mission concepts. Workshops are conducted by Caltech and JPL staff members, with a smattering of outside invitees included to give the patina of soliciting a broad range of ideas. Interestingly, two concepts coming out of Keck workshops drew the sudden attention of the keepers of our national space program: the human Asteroid Retrieval Mission (ARM) and the robotic Lunar Flashlight mission. Since these concepts were unveiled, the spaceflight community has been in turn bemused, amused and outraged. How does an idea (sometimes of multi-billion dollar scope) developed by a small group, with minimal input from the community at large, suddenly emerge as a national program? In the case of the ARM, it was a think-tank idea that fortuitously appeared at the right time.
In April of 2010, President Obama gave a speech on space policy at NASA’s Kennedy Space Center in Florida. In it, the President denigrated the idea of the United States returning to the lunar surface, advocating instead a human mission to an asteroid – allegedly as an interim deep-space step towards a human mission to Mars. It was quickly apparent that technical experts had not vetted this new policy idea and that its potential benefits (such as they are) were poorly articulated by the administration. Topping things off, no suitable near-Earth asteroid target – one that satisfied the various spacecraft, flight duration, abort and launch energy constraints – could be identified.
This was a serious embarrassment – a major re-vectoring of the human spaceflight program had been carried out by executive fiat with no suitable target destination identified (all dressed up and no place to go). Enter the Keck Asteroid Retrieval Mission. Since we cannot find a suitable asteroid to journey out to, it proposed hauling an asteroid back into lunar orbit and then going there to examine it. Never mind that the very idea largely negates the alleged principal advantage of an asteroid mission as a Mars precursor – to check out long-duration, deep spaceflight systems and procedures. Of course, one could accomplish such technology validation in cislunar space and on the Moon, but that uncomfortable fact would fly in the face of the President’s claim that there’s no national need to go back to the Moon because “We’ve been there.”
As far as scientific return goes, retrieval of an asteroid to lunar orbit does not advance the science of small Solar System objects one whit. We already have abundant samples of near-Earth objects in the form of meteorites, and we’ve conducted, or will soon conduct, extensive exploration of asteroids by a variety of robotic flybys, orbiters, landers and samplers.
To counter the growing chorus sharply criticizing the asteroid mission, and to obscure the many questionable judgments on display in the President’s 2010 KSC space speech, the ARM concept was eagerly seized upon by the agency. As a rationale for a strategic change in the national space direction, ARM is pretty thin gruel. Despite their best efforts to put lipstick on this pig, ARM continues to come in for criticism from a variety of directions, including former NASA management, space advocates, and the scientific community. In fact, about the only people strongly supporting the ARM are its original Keck workshop advocates.
A new robotic mission called Lunar Flashlight is another Keck workshop idea. This micro-sat mission concept involves sending a small package of cubesats (miniaturized spacecraft packaged as 10-cm cubes), along with a large solar sail, into lunar orbit. To look for evidence of hydrated material, the solar sail will attempt to reflect sunlight into the permanently dark areas near the poles in a bid to obtain near-infrared spectra of the soils in these craters.
Multiple scientific and technical issues can be identified with this mission concept. It is not clear that enough sunlight can be reflected into the permanently dark areas near the Moon’s poles to illuminate the soil and obtain good spectra from Lunar Flashlight. But more importantly, we already know from Lunar Reconnaissance Orbiter (LRO) laser altimetry that bright surface deposits occur in polar dark areas and that clear evidence of water frost is seen in UV imaging of some dark regions (although not in others). One of the biggest drawbacks to Lunar Flashlight is that a variety of evidence (including neutron spectroscopy and radar) suggests that much of the polar water on the Moon is found at depths of a few cm to tens of cm below the surface, thus rendering images of the surface spectra largely irrelevant to a quantitative inventory of polar volatiles.
In any event, Lunar Flashlight is a possible future robotic mission, probably because it is cheap (although no cost data have been provided as yet). The spacecraft launches as a secondary payload, hitchhiking a ride to GEO transfer orbit, whence it flies itself to the Moon. Lunar Flashlight is not the only possible lunar ice-detection mission considered in the Keck study, but reading through the workshop presentations illustrates a dearth of imagination. For example, the use of penetrators to obtain sub-surface polar information is discussed, but not hard-landing surface probes, cushioned by crushable enclosures. This may seem to be a “way out” idea in its own right, but this type of probe was built to fly to the Moon in the 1960s as a deployable part of the hard-landing Ranger spacecraft.
Given their influence on American space policy to date, one shudders to imagine what other ideas might arise from future Keck workshops – skywriting in orbit and hamsters to Jupiter are all in play. The space program is trapped in an irretrievable death spiral, where foolish ideas are pitched and adopted, then discarded as their public relations value declines once the concept is critically scrutinized. With each of these episodes, our nation and national space program lag further behind and lose more credibility. Instead of designing a technically credible space program that extends our reach into space, we are regaled with an endless parade of proposals for silly stunts. In regard to human spaceflight, we sometimes hear that “doing something” is better than “doing nothing.” Doing nothing might be a better option when the “something” being proposed is patently absurd. A static program might alert the public to what has been happening to our national space program.