#89 October 1995
Section 22.214.171.124.089.of the Artemis Data Book
"DUST CONTROL: Not all the physical aspects of the Lunar Environment that can fatally threaten a Human Basehold are Skyborne"
These particles are unweathered and thus have sharp edges. They include an abundance of micrometeorite-produced glass spherules. There is good reason to believe that without aggressive countermeasures and prophylactic strategies, they will accumulate in pressurized interiors to the point they foul up machinery, computer keyboards and mice, control panels and more. Some fear that inhaled moon dust could lead eventually, in extreme cases, to a sort of silicosis in the lungs.
Clearly, this is a potential problem of such scope that we cannot afford to treat it casually. It won't just go away. On the other hand, past human experience with sundry troublesome aspects of newly settled territories shows that most such problems soon become minor. We learn ways to deal with the problem that become second nature. In due course, bad effects diminish to the point where they are below the threshold of everyday concern. It becomes a matter of special habits - habits, if you will, of good housekeeping and good hygiene.
Moon dust, as a problem feature, would seem to be susceptible to a two-pronged approach: proper design of the structures and the equipment by which we interface directly with the host lunar environment. We must brainstorm our strategies well in advance of our return, adopting a broad spectrum of promising tactics in the design, deployment, operation, and maintenance of our outpost from the outset - or risk an ignominious, dishonorable surrender. Dust Control Strategy must be part of Moon Base Design.
Sinter-paved areas should be separated from untamed dust areas by access over grate-covered dust-moat trenches. The idea is to put the shoe- (and tire-) cleaning welcome mat as far out from the actual outpost entrances as possible.
Site Management must consist of more than fixing the regolith in entry apron and service areas immediately surrounding the outpost. Every regularly trodden and driven approach should be sinter-paved, by a method appropriate to the weight loads that will bear upon it. Pockets and preserves of natural moonscape terrain should be left for the areas and spaces between such paths. This will be a matter of landscape architecture and design in consultation with the Inner and Outer Yardmasters, to meet their needs. Ignore or dismiss all this and we will surely repeat the cluttered unkempt chaos surrounding McMurdo Sound in Antarctica.
There are limits to the effectiveness of such tactics. But without such dust containment zoning measures in place, anything else we try will not work at all.
Ben Bova, in his 1987 slow-selling Welcome to Moonbase*, describes a car-wash type air-lock in which incoming dust-laden astronauts pass through an electrostatic shower before entering the habitat proper. This would be an expensive piece of equipment, adding appreciably to the cost of lunar operations and settlement, if, as seems likely, it would have to be installed in each and every airlock! [* Ballantine Books, New York, ISBN 0-345-32859-0, $9.95]
Pat Rawlings, who did the illustrations for the book, has elsewhere illustrated a much better dust-control approach. The cover of Lunar Bases and Space Activities of the 21st Century** shows personnel wearing what I have come to call the "Turtleback" suit, in which an oval hardshell backpack covers the torso and back of helmet. This backpack is hinged on one side, and entry to the suit is made through the opening. [** W.W. Mendell, Editor; Lunar and Planetary Institute, Houston 1985, ISBN 0-942862-02-3]
In pre-release conceptual illustrations Rawlings did for the David Lee Zlatoff/Disney/ABC '91 movie "Plymouth" (still the only science fiction film ever made about settlement and the idea of using lunar resources), there are sketches of turtleback conformal airlocks (my words) into which this specially designed backpack makes a sealed connection, then swings open, allowing the incoming astronaut to (pulling his hands and arms out of the suit sleeves) reach back and up through the opening to grab a bar above the inner door of the lock and pull himself out of the suit and into the habitat. The suit and most of its dust remains outside, perhaps to be stored automatically on an adjacent rack. Whether Rawlings himself ever thought through his artistic concept this far, or further, is unknown to this writer. But we want to give him full credit.
We need to radically redesign both spacesuit and the airlock, co-defining and co-designing them to work together to keep dust outside all pressurized areas.
We will take up this idea and the several engineering challenges it poses in a separate article, hopefully next month after we speak on it at the upcoming MSDC and collect some helpful feedback. For now, we just wish to point out that we must totally rethink airlocks - and what we allow inside the habitat - as essential to successfully tackling the dust problem. And this promises to be a far cheaper approach, certainly in the long run. Such "suit-locks" will be features not only of pressurized habitat modules, but also of pressurized vehicles. It is a whole new language of how to handle the pressurized/vacuum interface in dusty locations on planetary and asteroidal surfaces. It is a language in which spacesuit and airlock are codefined and codesigned - far from the present case!
Contents of this issue of Moon Miners' Manifesto