Settlement Strategies

The colonization of Mars can be planned and performed in various ways. This article wants to line out basic colonization strategies with the final goal to establish a sustainable, self reliant Martian colony, that can exist and even thrive independently from Earth.

Aspect of physical independence

Introduction

The long term maintenance of complex equipment requires a huge number of persons. At a minimum, they will need to replace or repair critical components, such as life support, medical technology, food production, etc. It is hard to imagine that this can be done without electronics and chemistry. At least some technology must be maintained, for the Martian environmental conditions does not allow people to live naked on Mars. So, there is a critical mass for the number of persons in an autonomous colony.

Even if fully grown, a Martian colony is not considered a closed system without any input or output from and to Earth. It is rather an independent sovereign state, fully in control of its destiny. In that regard, it need not produce all of its needs locally. Even on Earth, no sovereign state would think of eliminating all trade with other nations. However, such a Martian colony can not perform a trade volume that is comparable with any state on Earth, because the shipment costs are bigger by several orders of magnitude. Therefore, the interplanetary commerce between Earth and Mars will be reduced largely to data and services that can be transmitted via a radio link.

Strategy 1: Independence step by step

An initial colony could start with a few persons. More colonists arrive later. In the beginning it does not supply all of its needs locally. Until critical mass is attained, the settlement will need to buy certain advanced technology. Interplanetary commerce is part of this strategy. It allows starting much simpler and earlier.

The first step is an Earth-supported colony. With further shipments it can be enhanced to a semi-autonomous colony. Finally the colony can be equipped with equipment for autonomous growth.

Strategy 2: Independence at once

Due to the risk of an interruption of the colonization program, this strategy aims at the full independence from the very start. The first settlement is built in a very spartan, but nonetheless sustainable way, with all vital supplies produced locally. This first settlement is constructed remote controlled and is fully functional before the first group of settlers head for Mars.

Spartan technology (and hence spartan standard of living) can reduce the critical mass. The inevitable food production is the most critical part. If that can be accomplished with simple technology, the critical mass could be small enough to gain independence at once. However, this includes mining and processing of all needed materials from local resources.

Aspect of transport and development

Introduction

To get an idea of the transport costs of a physically independent industrial infrastructure, the current industrial infrastructure on Earth may be estimated as 1 billion workers and 100 tonnes of structure, equipment, and spare parts per worker -- round the total mass budget to 100 billion tonnes. It currently costs $200,000 to land a kilogram on Mars. Additional infrastructure is required for Mars (e.g. pressure vessels and agricultural illumination systems), so double the infrastructure required to 200 tonnes per worker. That comes to 440 million trillion dollars. To reduce this cost by one or two orders of magnitude by creative selection of industrial equipment and workers is probably easy: some of Earth's industry is redundant in terms of self-sufficiency and thus required only for a population of billions. One or two orders of magnitude drop in transport costs may also be possible in the long term. But this only reduces the cost to at least 44 thousand trillion dollars. To reduce these costs to a reasonable sum, i.e. to the range of tens to hundreds of billions of dollars, requires radical reduction in the size of the industrial infrastructure required, which requires radical redesign of the technology (Strategy 1), or it requires further radical reductions in transport costs (Strategy 2), or a combination of both.

Strategy 1: Minimum transport and intelligent self development

Shipping costs are probably lower for small scale machines than large scale machines, and the financial frame will always be tight. The perfect, but unrealistic, way to colonize Mars is sending a one-kilogram probe with a handful of nanobots, preparing the whole colony, before sending a second one-kilogram probe with a handful of frozen fertilized human eggs, etc. This science fiction scenario is, of course, not realistic, but can serve as an ideal to strive for: minimize the mass and volume that needs to be launched from Earth, both initially and on an ongoing basis, by maximizing the self-sufficiency of Mars' industrial and agricultural infrastructures.

Strategy 2: Mass transport of ready-to-use technology

A colony needs large machinery for life support and further expansion. All machinery is shipped from Earth to Mars. Plans can be developed for massive colonization ships moving in repeated transfers between Earth and Mars without stopping. Only the cargo and passengers start and stop. Sending a complete industrial economy to Mars is theoretically possible. It just takes a long time, a launch volume much higher than current, or some combination of the two. See cost estimates above. For example, we might spend $100 billion per year for 4.4 million years to set up an independent Mars colony.

Strategy 3: Development industry on the Moon and then transport it to Mars

This is inspired by the 1970s plans of some futurists to build massive solar power plants to be built out of lunar materials. Removing the task of industrial development to the Moon mostly just switches the location of the problem. It still faces the same order of magnitude of transport costs from Earth(currently about $100,000/kg), and it may make the industrial development problem worse, because of the paucity of volatiles which are crucial and voluminous inputs to industry. It's easier to think about and solve the self-sufficiency problem in a volatile-rich setting like Mars.

Aspect of finance

Introduction

Frontier settlements are capital investments from which investors expect some utility. Rarely small amounts are donated to altruistic causes (e.g. expanding humanity). Governments invest small sums in science and larger sums in national security. Most commonly, investors demand a profitable return from their investments. The sooner a colony becomes financially self-sufficient, the less investment is required, and thus the sooner an investment is likely to be made in the first place. Since radical elimination of all imports is probably impossible in the short run (see above), a colony is much more likely to be financed if it can generate exports that match or exceed the costs of imports. Since imports are costly, the exports must be valuable. They must also be affordably transportable to Earth: high value and low mass.