Some Ethical Constraints on Near-Earth Resource Exploitation
One of the most common and enduring justifications for space exploration is that resources are limited here but plentiful elsewhere. Exploration has the potential to enable humanity to access the vast store of resources throughout our solar system. Recent discussion (driven to some extent by U.S. legislation and by speculation about the future role of the private sector in space) has tended to focus on what we shall call “near-Earth resources” (NERs), which include those of the Moon and near-Earth asteroids (NEAs). They include: potentially vast stores of water, iron, and platinum-group metals among the NEA population; so-called ‘peaks of eternal light’, i.e. places of uninterrupted sunlight (for solar energy collection) and crater areas in more or less permanent darkness (able to harbour water ice) on the Moon; Helium-3 (He3) in the lunar regolith; and the relatively banal resource of terrestrial orbital niches. What is often lost in the enthusiasm concerning such NERs is that, in spite of the immensity of space, only a small percentage of the NEA population is profitably accessible in the absence of distant, futuristic technology; only so much of the lunar surface (or elevated areas just above it) is permanently illuminated (or shadowed); the He3 concentration in the lunar regolith is very low, geographically differentiated and reduces with depth (the regolith on asteroids is also likely to be less mature and so He3 concentration levels are likely to be even lower); and, as is already well-known, there are only so many available orbital allocations. These practical realities suggest that issues of sustainability will not vanish during at least the early stages of space exploitation, and perhaps at all stages for the foreseeable future. They do not support unrelenting and unregulated utilisation and consumption. In fact, quite the opposite.