Absent significant innovation in the technologies that facilitate space travel, all human life will end. Earth has already experienced five mass extinction events in the 3.5 billion-year history of terrestrial life. The next mass extinction may, potentially, wipe out advanced human civilization. Many experts think climate change presents a serious threat to human life; others fear asteroid collisions, supervolcanoes and solar flares. And even if our resilient species adapts to apocalyptic conditions on Earth, virtually all astronomers and physicists agree that eventually — in roughly 10 billion years — our sun will die.
The death of the sun, which provides the necessary energy for every ecosystem, promises an end date to terrestrial life. Indeed, while it is unclear precisely when, it is certain that human life will someday be impossible on Earth. Thus, to accept Earth as the constraint for human life and civilization is to accept the inevitability of human extinction. Unless our species becomes multiplanetary, mass extinction awaits. Consequently, space exploration is a prerequisite for the continuation of human consciousness and ought to be a priority for both public and private actors. The light of consciousness as we know it, whatever its constitutive properties may be, will meet a brutal end unless humanity becomes a sophisticated spacefaring civilization.
Space innovation is an ethical imperative because species extinction precludes all other ethical considerations. While we can debate the relative merits of investments in projects aimed at alleviating disease, poverty, and war — and all are critically important debates — these projects become futile if species extinction is inevitable. Oxford professor and philosopher Nick Bostrom writes in “Existential Risk Prevention as Global Priority” that “the expected value of reducing existential risk by a mere one billionth of one billionth of one percentage point is worth a hundred billion times as much as a billion human lives.” In other words, the gravity of a legitimate existential threat is so severe that even a low-probability existential threat is more dangerous than a certain but non-existential threat.
If humanity remains constrained to Earth alone, both the scale and probability of threat to life is tremendous. That’s why Bostrom concludes that, “reducing existential risks should be a dominant consideration whenever we act out of an impersonal concern for humankind as a whole.” Indeed, all of our policymaking decisions, ostensibly resting on value judgements measured by conceptions of ethics, presuppose the value of human consciousness. When considering the grand scope of the history of the universe — billions of years behind us and trillions more ahead — the ethical considerations of a solely Earthbound civilization become wholly insignificant. Thus, because an Earthbound humanity necessitates the end of consciousness, ethical policymakers must move beyond the bounds of Earth.
Fortunately, a multiplanetary future is possible, giving conscious life the tools to survive when Earth can no longer accommodate that life. In our immediate vicinity, there are five clear targets ripe for settlement: our moon, Mars, two of Saturn’s 82 moons — Enceladus and Titan — and one of Jupiter’s, Europa. With already existing technology, each site could, in principle, accommodate human life, albeit with support from Earth. This is a necessary first step before off-world settlements become self-sufficient.
Humanity may begin building permanent settlements near to Earth, mastering space transportation as settlements pursue self-sufficiency. Advanced space stations, children and grandchildren of the International Space Station, may also enable interstellar habitation, travel and trade. And as our population spreads across the solar system, we should also reach beyond — sending robotic scouts and eventually manned missions to explore surrounding systems.
A multiplanetary future is already within reach. Elon Musk and Jeff Bezos, the two wealthiest people in human history, opt now to spend most of their time in the space economy. While some consider their efforts pure vanity, the truth is that both businessmen are making an investment in humanity’s future. Already, SpaceX demonstrates mastery of reusable rockets, a critical technology for a multiplanetary future. And further innovations are soon to follow. Let’s not forget: just over one century ago, modern wonders we now take for granted — air travel, nuclear power, the internet, and robotics, to name a few — were relegated to comic books and science fiction.
To expedite the advent of multiplanetary civilization, world governments should join the entrepreneurs, dedicating more resources to research and development in space. Public-private partnerships should be leveraged to help governments narrow their capabilities gaps. Luckily, already existing national and international space agencies provide a useful starting point. But world regimes must also establish new entities. Indeed, a sophisticated institutional apparatus for spacefaring life will be critical for multiplanetary civilization.
But more importantly, and even if success were less probable, space innovation would still be our species’ ethical imperative. If we can’t figure out how to live beyond Earth, conscious life as we know it will end. And there can be no ethics without consciousness.