An artist's drawing of a moon colony: a futuristic building on stilts and a person in a spacesuit.
NASA file image: An artist’s rendition of a moon colony.

CLEMSON, S.C. — Space might be the final frontier, but as China announces plans to build a moon base, NASA begins working on manned missions to Mars and spaceships continue to probe deep space, one group of scholars is asking: are human colonies in space ethical?

“As long as space colonization was merely the dream of science fiction fans, serious questions about how and if we should do it were moot. However, now that colonies have become a near-term possibility, the question of whether and how we ought to build them becomes pressing,” says Kelly Smith, a philosopher and biologist at Clemson University and founding president of the Society for Social and Conceptual Issues in Astrobiology (SSoCIA).  Smith and Keith Abney, a philosopher at Cal Poly, co-edited a special issue of the academic journal Futures devoted to exploring these issues.

Topics like the immediate and irrevocable impact humans will make in space were missing from the discussion until recently.

“Now, astrobiologists are looking for fossil evidence of past life on Mars, and the possibility that Mars might host microbial life today is growing stronger,” says Linda Billings, a consultant to NASA’s Astrobiology Program and the Planetary Defense Coordination Office. “Once humans land on Mars, the environment will be contaminated for further scientific exploration.”

In a special issue of Futures, Smith, Billings and 14 other scholars address space colonization from their a variety of disciplines: philosophy, communications, ecology, animal rights, anthropology, and religion. The essays are a collective call to “incorporate the ethical dimensions more explicitly in our decision making,” Smith says.

Billings says the essays “are intended to enrich the current dialogue about the future of Mars exploration.” She and Smith both hope NASA and other space agencies around the world take up the conversation.

“We need more study of the issue before we get too far ahead of ourselves,” Smith says.

The journal essays sprung from discussions leading up to the second biennial meeting of the Society for Social and Conceptual Issues in Astrobiology (SSoCIA), an organization dedicated to interdisciplinary discussion of the many broader issues posed by astrobiology and space exploration more generally.

“Several SSoCIA members began an intense email exchange over the propriety of human colonization, which led to an intense panel discussion at the 2018 conference that was as stimulating as it was frustrating – stimulating because it involved an engaging exchange of radically different points of view, but frustrating because it barely scratched the surface,” Smith says.  “The special issue is an attempt to share the spirit of these exchanges with a wider audience.”

In an “interactive” essay, “The Great Colonization Debate”, all 15 contributors explore the broad contours of the debate in an informal, freewheeling, fashion, Smith says. It addresses six central questions:

  • Is there a moral duty to preserve humanity through colonization?
  • Is any such duty contingent on the good behavior of humanity?
  • Is colonization, in the long run, a good or bad thing for Earth’s other inhabitants?
  • Given this discussion, what goals should we be pursuing with respect to colonization right now?
  • What alternatives to the traditional model of colonization should we pursue?
  • Is it morally permissible to send humans into what is likely to be a hellish situation?
A NASA composite image of Mars.
A 2006 NASA composite image of Mars.

On one side of the continuum, some people argue that humans have no business in space until and unless they prove they can manage the Earth responsibly. They believe that public opinion concerning colonies is driven by a largely uncritical acceptance of ideologies of conquest and domination, which should have no place in the debate.   They also point to humanity’s abysmal environmental record on Earth and ask if we have the right to subject another world to our destructive presence.

Others counter that colonies in space may be the best long-term chance to save humanity, and non-human species as well, from ultimate disaster. If we have moral obligations to do anything, this group says, we have a strong obligation to preserve humans – the only beings known to be capable of moral reasoning.

“How much does ethics demand of us before we make humanity a multi-world species?” Smith asks. “A lot, since the bottom line is that no serious discussion of human colonization can proceed responsibly without careful and systematic consideration of these sorts of ethical concerns.”

The essays are:


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