FORWARD by Peter Kokh
On our long drive home from the Denver International Space Development Conference in May of 1988, I told some of my fellow Lunar Reclamation Society members about my general idea and what might be possible farther in the future. So this January when the chapter's new think tank, Milwaukee Space Tech(nology) & Rec(reation) - MilSTAR - decided to take Seattle Lunar Group (SLuG)'s Joe Hopkins up on his challenge to enter the NSS 1000-5000 person Lunar Base Design Competition, a rille site became our instant choice. [MilSTAR was later playfully renamed Copernicus Construction Company]At the 1989 International Space Development Conference in Chicago, the Competion winners were announced. We placed second (to an architecture student whose entry did not satisfy the constraints and conditions - but he was an "architecture student"). In our minds, our entry was clearly superior. But we were delighted to receive the second place award, handed us by Hugh Downs.
Part I: THE RILLE AS A SETTLEMENT SITE Part I previously published in Moon Miners' Manifesto #26 June 1989
by Peter Kokh
I can remember the days when I used to look upon lunar rilles, great winding valleys hundreds of meters wide and deep and sometimes hundreds of kilometers long, as unfortunate road hazards, obstacles to easy transportation across otherwise flat lunar seas. Every time you plotted a logical route from point A to point B, sure enough there would be some lousy rille that would make it necessary to detour and zigzag or take altogether circuitous routes. While I have a lifelong habit of staring apparent obstacles, disadvantages, and liabilities in the face until I see in them some hidden asset worth turning into a trump card, I was slow on this one.
In trying to imagine the Moon as multi-settlement world, I have repeatedly scouted the maps, photos, and globe for special assets unique to particular sites, giving them raison-d'etre [reason for being] as potential sites for human presence. The Moon is seen by almost everyone as a dull monotonous place. But don't let yourself be fooled. The seeds for diversified and varied human presence are there. Clues abound. Someday I'd like to write a book for amateur observers and armchair dreamers "Looking at the Moon with a Settler's Eye."
Having plotted, in my mind's eye, half a dozen logical yet uniquely advantaged sites for traditionally conceived cities dug into the surface, and looking further into the future to a time when one didn't have to be so stingy with nitrogen (believe it or not, nitrogen for the inert component of air, not hydrogen for water and biomass, nor carbon, will be the most critical and decisive of the Moon's several deficiencies) and could plan something with vista-friendly headroom, the idea of covering a rille finally burst in my lethargic brain. Covering a rille, spanning as much as a kilometer, should not be an impossible engineering feet in lunar sixthweight, where there are no winds to blow and no quakes above an impotent 2 on the Richter scale. The building materials are already on site. But all the tons of nitrogen needed to co-pressurize such a volume! That's the stickler.
I imagined a long sinuous 'national park', a wildlife refuge in which now native Lunans could go to gawk and grok, in Schroter's Valley (not the 15 km wide main valley but the narrow rille within a rille that runs down the center - you need a good photo to see it). Maybe in the 22nd Century something like that would be possible.
Meanwhile, more modest structures could be built in rilles. Why? Because rllles have sides! It's as simple as that. Rilles have sides, that would otherwise have to be human-built. Why, a rille is an excavated foundation just waiting for construction!
In Welcome to Moonbase by Ben Bova (1988, Ballantine), Eagle Engineering's Pat Rawlings depicts large volume structures built on the Moon, requiring lots of excavation plus the hauling of a lot of shielding material up onto the clearspan shell. [The same drawings and art were used by the ill-fated Lady Base One Corporation. ] It was a bold yet quixotic concept. In contrast, rille sites offer pre-excavated sites and the opportunity to pull shielding soil down upon any structure built in the lower portion of the rille.
By virtue of its flanks, a rille site offers a vastly greater heat sink [the temperature of the soil below the first couple of meters is steady -4oF = -20oC all month long - all year long]. By the same token, from vantage points along the bottom, appreciable fractions of the sky that would otherwise be above the horizon are eclipsed by the rille sides. Consequently there is even less exposure to general cosmic radiation [Lunar sires, having their butts coveted by the soil below, have only half the exposure that space colonies will have].
Sinuous rilles often do not occur as isolated features. They are, after all, collapsed lava tubes. It is common to find a complex of rilles, partially collapsed lava tubes, and (by inference) uncollapsed suspected integral lava tubes, all radiating outwards down the gentlest of slopes from the principal sites of the great magma (lava) upwellings that filled the vast lunar impact basins forming the 'seas' so familiar to us. A well chosen site should offer considerable regional expansion opportunities.
We have high resolution orbital photos of several such features. David Scott and James Irwin of Apollo 15 explored a section of Hadley Rille from their lunar rover in late July, 1971. It was their photos that fueled my imagination. We wanted a rille segment that ran in an East-West direction to maximized the amount of sunlight available at the bottom of the rille during dayspan. After a search of photographic atlases of the Moon, we settled on a rille just north of the partly flooded crater Prinz, near Aristarchus.
PART I - A Settlement in a Rille Valley