Moon Miners' Manifesto

#99 October 1996

To / From the Lunar Surface

Peter Kokh

Relevant Readings From MMM Back Issues

MMM # 6 JUN '87 "Bootstrap Rockets"
MMM # 55 MAY '92 "A Better Slide-Skid Lander? Enhanced Harenobraking"
MMM # 56 JUN '92 "Harbor & Town"

How do we cut expenses for landing on the lunar surface? Use as low-mass a landing vehicle as possible to bring down the equipment, supplies, people, etc. Leave unneeded mass in orbit. See last article. In addition, we can pursue these strategies.

Fuels and Oxidizer from Moondust

• Liquid Oxygen for fuel oxidizer is the most obvious opportunity to save. There are many ways LOX can be processed from the lunar regolith soil. "LOX" can even be used to refuel Moon-bound vessels in low Earth orbit.

• Less potent but quite adequate, powdered metals (alone or in a liquid hydrogen slurry) can be used in place of hydrogen. Abundant lunar aluminum, iron, calcium, and magnesium will do well. Aluminum oxygen combination is the most potent but it will take a lot of equipment and energy to produce the aluminum powder. (A 75% aluminum, 25% calcium alloy is be easier to keep powdered). Pure iron powder is everywhere, especially on the mares, and can be produced easily by passing over the soil with a magnet. The exhaust is rust powder which will fall harmlessly back to the surface without degrading the lunar vacuum.

Densifying Hydrogen Extenders

Economic pressures (impatience for short term advantage and profit at the expense of long term sanity) to use precious lunar hydrogen reserves directly will abound and there are many "damn the future" space advocates ready to do just that - some of them prestigiously placed. By treaty or lunar charter, it is in the interest of future Lunans and their civilization to restrict such use with adequate safeguards and stiff penalties. Landing without Retrorockets

Mars fans are quick to point out that thanks to its atmosphere, it will be cheaper to land people and cargo on Mars than on the Moon. But there are a few tricks other than aerobraking that can be used on the Moon in similar fashion.

• Krafft Ehricke described a "Lunar Slide Lander" that would dump horizontal momentum into a prepared regolith runway in Lunar Industrialization and Settlement - Birth of Polyglobal civilization" in "Lunar Bases and Space Activities of the 21st Century" ed. by W.W. Mendel, Lunar and Planetary Institute, Houston 1984, pp. 825-7.

  In what we hope is an improvement on this idea, Doug Armstrong and I published an article on "Enhanced Harenobraking" [sand-braking] in MMM # 55, cited below. It is conceivable that some limited application of this trick could be used to shed some of the momentum of an incoming personnel carrier.

• Cushioning Farings of non volatile material - e.g. metal and ceramic foams might land G-hardened payloads on the Moon intact, in specially restricted landing zones where they can then be "harvested".

• Chicago inventor Ed Marwick has put forth an elaborate proposal in which guided payloads enter a sloping chute dug into surface and encounter ever denser sprays of regolith dust, slowing the capsule down to a halt. Such a facility would have to be as long as a mass driver per level of Gs to be tolerated.

Loading and Unloading Facilities

Electromagnetic Launchers

Other elaborations are possible:

• value-added pelletizable processed materials
• G-hardened small size manufactured items
• Larger items (cargo holds, personnel pods) in more potent, longer, slower accelerating launch tracks

Reversing mass drivers or Mass Catchers which catch and brake landing payloads have been mentioned and need further investigation for high traffic situations. In most cases this will not require a new facility, just a new "reverse" mode use (where launch demand allows) for an existing mass driver.

Mass Drivers-Catchers are expensive big ticket items. They will lower costs to and from the lunar surface only when amortized over a long period of high traffic use. MMM

Contents of this issue of Moon Miners' Manifesto