It's obviously far easier and cheaper to fix the problems of this planet than to find a way to live off-Earth. What are the challenges that might make us want to find a new home in space? The ultimate demise of Earth will occur in four billion years when the Sun runs out of its nuclear fuel. At that point, the Sun's core will collapse and the star's violent reconfiguration will eject a layer of gas that will engulf the Earth and cook the biosphere. But long before that, the Sun will start to burn hotter as it consumes its hydrogen; about half a billion years from now, the temperature on Earth will have risen enough to make the oceans boil. Those timescales are long enough that we might be forgiven for not getting too worried.
The best metric for proximate danger is the Bulletin of the Atomic Scientists. Starting in 1947, a group of scientists and engineers created the Doomsday Clock to show how far we were from apocalypse. As the threat of nuclear holocaust receded, the proximity of the clock to midnight started to take into account the possibility that through climate change, biotechnology, and/or cyber-technology we could cause irrevocable harm to our way of life and the planet. The clock sat at two minutes to midnight in 1953, at the nadir of the Cold War. In 1991, it receded to seventeen minutes to midnight with the fall of the Soviet Union. In 2012, however, it read five minutes to midnight because of a surge of nuclear weapons in the hands of small, unstable countries, and the sense that climate change may have passed a tipping point.
Many voices have weighed in on the subject of leaving the Earth. In 1895, the rocket pioneer Konstantin Tsiolkovsky said, "Earth is the cradle of humankind, but one cannot live in the cradle forever." Carl Sagan put it this way a century later: "Since, in the long run, every planetary civilization will be endangered by impacts from space, every surviving civilization is obliged to become space faring — not from exploratory or romantic zeal, but for the most practical reason imaginable: staying alive." Science fiction writer Larry Niven was more succinct: "The dinosaurs became extinct because they didn't have a space program." We may be able to fend off impacts from space, but physicist Stephen Hawking sounds the alarm about other threats: "It will be difficult enough to avoid disaster in the next hundred years, let alone the next thousand or million. Our only chance of long-term survival is not to remain inward-looking on planet Earth, but to spread out into space."
A mass exodus from Earth is implausible. After all, it costs $50 billion just to send a dozen people to the Moon for a few days. SpaceX founder Elon Musk may claim he'll reduce the price of a trip to Mars to $500,000, which is a hundred thousand times less, but that seems unlikely at the moment. If the Earth becomes contaminated or inhospitable, we'll have to live in bubble domes, fix it, or suffer through it. Nonetheless, in this century a first cohort of adventurous humans will probably cut the umbilical and live off-Earth. What issues will they face?
Beyond survival, their first issue is their legal status. The 1967 Outer Space Treaty addresses ownership. According to Article II, "Outer space, including the Moon and other celestial bodies, is not subject to national appropriation by claim of sovereignty, by means of use or occupation, or by any other means." That seems transparent, but it doesn't mention the rights of individuals. Bas Lansdorp, the CEO of Mars One, said his legal experts looked into the treaty. He thinks that "what goes for governments also goes for individuals in those governments." If Mars One achieves its goal, thirty people will settle the red planet by 2023; the gradually expanding settlement will use more and more Martian land. Lansdorp insists that their goal isn't ownership. "It is allowed to use land, just not to say that you own it, Quot; he says. "It is also allowed to use resources that you need for your mission. Don't forget that a lot of these rules were made long ago, when a human mission to Mars was not within reach."
Some space players claim altruistic motives, but none of them can succeed without revenue to fuel their dreams. What happens when profit is the only goal? Large multinational corporations are bound by international trade law, but they could plausibly argue that they have the right to use, even to exhaust, the resources of an extraterrestrial body. A government that wanted to appropriate land on the Moon or Mars might withdraw from the Outer Space Treaty, and it's unlikely it would suffer any serious consequences. Even Mars One exists in a legal limbo. Bas Lansdorp needs to fund his $6 billion mission: "Imagine how many people would be interested in a grain of sand from the New World!"
At some point, the debate will stop being hypothetical. The history of colonization of the Earth shows that a claim of ownership is irresistible. Each succeeding generation of settlers who are born and die beyond Earth will feel less connection to the home planet. They are likely to chafe at the rules and regulations imposed from afar. Tanja Masson-Zwaan, deputy director of the International Institute of Air and Space Law and a legal adviser to Mars One, says, "I assume at some point these settlers will become more detached from Earth, and will live by their own rules." The historical example of Manifest Destiny is misleading in the context of space colonization. Countries have grown and gained resources on Earth by seizing territory and displacing or subjugating the original inhabitants. Even in the twenty-first century, the stains of this brutal history persist. Space is a new resource. The people who leave Earth won't be taking land from anyone. Eventually, they'll have to make everything they need to survive and prosper. They will create their own wealth. It will be hard to hold them to any Earth-centric legal framework if they want to be independent.
Colonization implies replacement and growth. A Mars colony can be augmented by new arrivals, but a healthy, normal culture centers on the family unit. There will be sex and there will be babies. Sex in space hasn't progressed beyond snickering and titillation. It's the stuff of urban, orbital legend. Every couple of years, NASA and its Russian counterpart wearily deny that astronauts have had sex. The astronauts themselves stay tight-lipped. Official policy forbids it. Martian sex presents fewer obstacles. The 40 percent gravity would require minor adjustments. To finesse the issue of procreation, if not coupling, all-male or all-female crews have been proposed. More controversially, voluntary sterilization has been suggested for the first colonists. Mars One plans to arm its colonists with contraceptives, but it's not known how well they would work on Mars. The first waves of Mars colonists will die there, and they know that the medical facilities will be rudimentary; they're unlikely to want babies. But as colonies get established, the dictates of biology and human culture will prevail.
Imagine when the first baby is born off-Earth. That event will be an extraordinary milestone, resetting the clock of human existence. In Arthur C. Clarke's short story Out of the Cradle, Endlessly Orbiting, an engineer at a Moon base is preparing to relocate to Mars when his wife goes into labor. The baby's first, plangent cry shakes him to his core, resonating more than the roar of any rocket ship.
Nuclear weapon test Romeo (yield 11 Mt) on?Bikini atoll. The test was part of the?Operation Castle. Romeo was the first nuclear test conducted on a barge. The barge was located in the Bravo crater. Click here for original source URL.