Moon Colonization

Moon colonization is a complex enterprise, requiring detailed planning, research and development. We favor a forward looking perspective, with regards to the actual science and engineering required to fulfill the goals of such a project. We especially favor any science, and engineering research and development, which gives priority to design choices linked to notions of modularity and extensibility. We also favor opting for the more expensive design choice; if that choice is based on third millennium technology and material, and is no more than 20-30% more expensive than less up-to-date technology.

The forward looking choices and requirements are the following:
A second generation shuttle, with a two-week turn-around time per trip; a new fuel for space-based travel; a cargo train made up of wagon-like sections; a modular, paneled design for moon habitats; a new version of LEM vehicles, one for cargo downloading, and another one for people downloading;  wherever a way of doing things can be automated; it should be done; thereby removing the human factor from most considerations; and finally, no more than 1 astronaut death per 20 years.

A Possible Plan

Second Generation Shuttle

The second generation shuttle should be smaller, coming in two versions. One with a cargo section for transporting small payloads, with or without cargo bay doors like the shuttle. The second one, with passenger space, is for solely the transport of astronauts. A tentative design of the new shuttle results in a wide-bodied aircraft, which looks like a cross between a Galaxy transport aircraft and the Raptor fighter plane. All the mass of the aircraft is found below the wings, and is made of two levels. The top level is the cabin level, and the bottom level is for cargo space or engines.

The overall shape of the new shuttle ensures a flushed integration of the wings with the body; where body and wings are seen clearly as separate structural elements, which we believe, after testing, should make flying the aircraft, by the flight computers, easier. The under body of the aircraft, and its integration with the wings, should be designed to provide additional lift capabilities.

The third generation, of an updated space shuttle, will house in the bottom level, instead of a cargo section, a scram-jet in the center, and a jet engine on each side, or Hotol type engines, plus fuel reservoirs. Other types of possible engines are pulse detonation engines and pulse-mode plasma engines, which are yet to be designed.

The second generation shuttle additionally provides placement, on top of the wings, for  rockets which may be required for the final push into space. The wing shape should be triangular, as in the raptor. Aileron placement, whether vertical, slanted, or horizontal, is to be decided, based on their effectiveness in providing close to airliner stability, in final approach and landing -- stall speed must be lower than that of the current version of the shuttle. Vertical, or slanted ailerons, and tail assembly must not get in the way of the rocket, or rockets required for last push into space, or possible cargo bay doors.

A new form of aero-gel, which is strong on all angles, can be used for the interior paneling of the shuttle; as well as, for seats and floors. The first generation will use mostly carbon fiber. The use of plastic is avoided, because of questions about its long term longevity, and possible noxious degradation, in space. Areo-gel is used for electrical conduits to minimize the spreading of possible electrically caused fires. It is also used for sound cloaking of the cabin, passenger, and the engine sections.

High-grade ceramic should be used for exterior heat shielding. The carbon tile heat shield should be kept, as a middle heat shielding layer; and the last layer should be a ceramic one, burned into the aluminum/titanium frame. The frame, itself, is built as a single unit, using meld welding.

The alternative to using a solid external high-grade ceramic layer is to use a softer one, which sublimates at high temperature in a uniform manner. The sublimation must be uniform, in order to prevent the shuttle from being destabilized at supersonic and hypersonic speed. Only a tiny layer should sublimate on each re-entry. After each trip, the shuttle could be wheeled into a hangar; where robots could re-apply a new coat of the soft ceramic compound, while diagnostics are performed, on other systems of the shuttle. The process should take no more than 72 hours; and the rest of the week is to address problems that the diagnostics routines could have uncovered. The harder coat alternative is a way to keep a shuttle in circulation, as long as, possible; therefore, a shuttle would have to be taken out of circulation, for at least a few months, for refurbishment.

Cargo Train

The idea of cargo train service, probably supplied by a private company, is to ensure, that an appropriate amount of cargo always reaches the astronauts; since, we expect that a substantial number of them may be posted on the moon (100 or more), five years after the first launch.

The cargo train is made of 10 to 15-meter sections, some radiation shielded, some not. The shielded ones, can be fully shielded, and used as, additional cabin space for astronauts, for a week-long trip to the moon; as long as, the required thrust can be achieved.

A walker robot is needed for loading and unloading cargo on and off the train. Each cargo section, of the train, has only a side door/hatch, large enough for the biggest possible crate. The option of having a cargo bay just like the shuttle was not an option. Crated cargo is stored on a motorized setup on the floor of the section; which is able to move selected crate to the front before the hatch; waiting to be grappled by the robotic arm. Cargo should be carried in re-usable, shielded, tagged, and weight-calibrated crates, with transponders. All the research and development can be done by a private company. The sections can be launched into space, with heavy-lift, Atlas-type rockets.

At each end of each section there should be an armored layer made of Kevlar, ceramic, or any new material which can prevent damage to the vulnerable parts of the train, due to an explosion of the rocket module, or to impacts by space debris.

Recycling Cargo

Recycling cargo and empty crates back to Earth, could be done by using a guided-munition type of re-entry vehicle. The re-entry pod could essentially be egg-shaped or oblong with stubby wings which are retractable or not, depending on their heat profile. The stubby wings could double as air-brakes. The pod should be unsinkable, to allow landings in water, with the use of a parachute.

Rocket Module and Fuel

Two sections are required for the rocket and fuel module which will push the train to the moon. A new type of fuel, which is safer to store and handle, over a long period of time,  is the first question mark in the project planning. This new fuel is only required for space-based transportation.One possible option is the use of methane clathrate, as a fuel, which has the consistency of slush at low temperatures. Methane clathrate would be ideal, as a fuel, if a high-speed way to split the water shell into oxygen and hydrogen could be found. -- for fuel chemists to research and develop -- A Methane-hydrogen mix could also be considered; whereas, kerosene and hydrogen could pause a problem with frequent refuelings.

Combustion type rocket engines can be avoided altogether, by adopting plasma-type rocket engines.

The rocket modules design can be done by a private company. The requirements to be satisfied are the capability to push a 100-150 meter train to the moon in a 28-day trip; a short train in 7-days, a very short one, the same time, as the Apollo missions.

The Downloaders

The downloaders are the second question mark in the whole enterprise. The question is, whether or not, the appropriate rocket engine can be developed to provide for a re-usable, reliable, safe vehicle, which can take-off from the moon, after re-fueling; and, download cargo and people, in a safe, automatic pilotable fashion, as a single unit.

People Downloader

The people downloader should be fully automated. It should be able to take off and land, given origin and destination coordinates. The LEM should be able to automatically gauge the total load, and fuel requirements; as well as, plan its own trajectory, from origin to destination. It should be able to take-off and land as a single unit. It should be fully shielded, and able to carry 2 to 3 astronauts. It should be easily, and safely re-fuelable, on the moon and in space. It should be able to position itself safely near a train, to be grabbed by a robotic arm. The robotic arm can then move the LEM near a hatch to an habitable section of the train. The LEM should be able to dock with an habitable section of the train, or vice-versa.

Cargo Downloader

The cargo downloader is essentially, a carrying platform, a stripped down version of the people carrying version. It should also be able to position itself safely near a train, to be grabbed by a robotic arm. The robotic arm can then load an appropriate number of crates on the LEM. It should take the robotic arm a specified amount of time -- for engineers to estimate -- to load and unload cargo from the LEM.

Moon Habitat

The habitat must be modular, using panels for construction. The panels must be fully shielded, and use vacuum seals as latches. The vacuum seal mechanism must be able to be powered by a fuel cell, requiring just an adapter. The adapter should always be in the control of the commander of the mission, or station. The panel must not exceed a lunar weight, that an astronaut could not handle alone. The base and walls, of each habitat, are built with the same type of panels.

A set of habitats can be built, essentially, as a honeycomb structure -- left to architects and engineers to research and develop. The paneled habitats must be able to handle condensation, without a filtering mechanism -- the panels themselves must be engineered appropriately. The filtering mechanism must handle condensation, sweat, water vapor, lunar sand, etc.. To reduce the impact of lunar  sand; the hatch of every habitat must have efficient sand filtering, to prevent said sand from entering the main area of the habitat. A habitat model can be tested in Antarctica, during the winter months, to examine the effects of cold and wind pressure, on the vacuum seal mechanism; as well as, gauge to what level does condensation rise, inside the habitat.

Habitat Location

The location of the habitats should preferably be chosen in the 5-10 KM ring along the dark side.
The habitats would not be constantly exposed to solar radiation. The resources needed for the permanent and non-permanent colonies must be in the 5-10 KM ribbon, if not a larger ribbon would be required, as others would suggest. Radiation shielding for other than habitats would not be as necessary since some elements could be buried; such as electricity carrying cables. Also sections of colonies that are not constantly occupied by people, would also not require as much radiation shielding. If radiation shielding is cheap, than shielding everything is preferable.

Kilometer-square fields of solar panels can be setup; and miles of cables can be used to carry the electricity to the habitats. The secondary supply of energy should come from fuel cells and hydrogen/oxygen canisters. An adiabatic generator could also be used, located in the ribbon,
where one end would always be exposed to the sun and the other not; to be able to use the more than 200 Celsius temperature differential, for energy generation; the inside of a wide crater which provides the required shading is also a possibility. The compound used, in the adiabatic process, would not need to be ammonia-based, and must not freeze when not in sunlight.

Our moon version of an adiabatic system, differs from the usual ammonia-based one. The system
envisioned for the moon, essentially uses the temperature differential between a cold and hot zone, approximately -100/-200C to -100/-150C, to create a convection current using a given gas, in our case nitrogen. Our system is called the Π-generator; and is a closed-system energy generator.
It utilizes turbines housed in a cylindrical chamber or tube. The cylindrical chamber may range from a few meters to ten of kilometers. Nitrogen gas is used to fill the chamber, and a suction pump is used to move the heated nitrogen gas from the hot zone to the cold zone. A minimum speed must be maintained which is equal to the cut-in speed of the turbines. The length of the tube, we envision for the moon, can range from five to fifty kilometers. The turbines, depending on their design, can be spaced from five to twenty meters, see patent-pi-generator for an earth version.

The downloaders should always land, as least the distance that debris from an explosion would travel, from the habitats -- for engineers to estimate.

Bone/Muscle Loss and Retention

The negative effects, such as bone and muscle loss, of remaining in space for a long period of time, can be remedied in two ways. One is a biochemical answer, which would provide a pharmaceutical-based treatment. Such treatments would consists in injecting a compound into bone cells, to trap calcium, and preventing it from leeching out of bones. The second is a mechanical answer, which consists of using a rotating sleeping compartment, akin to a mouse wheel; providing sleeping space for two astronauts, in a hammock-style resting position. The mouse wheel would rotate, around a transmission-like axle, and have two counter-balancing weights, at each end of the axle; to offset any difference in weights of the sleeping astronauts.

The transmission, in its neutral state, must reduce friction to a minimum, through the use of friction-less bearings or surface, e.g. ice surface, for plates connecting axle and wheel, or/and load bearing surface for wheel rotation; so that the mouse wheel, once accelerated to a given speed, can keep rotating, for as long as possible. The transmission, itself, can be replaced, by rail gun-type acceleration.

The energy necessary for the mouse wheel engine can come from fuel cells or solar panels, and must be separate from a space station's power supply. The mouse wheel concept is simpler and more easily developed than a Ferris-wheel habitat concept. The mouse wheel concept also answers, both, the bone and muscle loss problem; whereas, the pharmaceutical answer would only solve the bone loss, and not the muscle loss problem.

Because of possible vibrations coming from the engine; mouse wheel sleeping compartments should only be located in non-work modules of a space station, craft, or train.

Pierre Innocent