Years ago I read a book called The Millennial Project by Marshall T. Savage. It was a brilliant, creative, and comprehensive step-by-step plan to colonize space. I’d still recommend it to our elected governments, private interests, and anyone else interested in preserving Life by seeding it beyond the confines of Earth. The book’s offspring, the Millennial Foundation, is still around (although renamed the Living Universe Foundation) but its progress has not been newsworthy and Savage is not even active with it anymore. Nonetheless, the core reasons for colonizing space and other planets remain: 1) The human population is too high—the planet can’t sustain us. 2) Human life, and all earthly life, is just too vulnerable on this single planet. Depending on which scientists you talk to, there have been anywhere from a handful to more than twenty “mass extinction events” in the history of life on Earth. The asteroid QE2 passed within six million kilometers of the Earth last Friday—not especially close, but it was as large as the asteroid that’s thought to have killed the dinosaurs. They’re out there. We should be too, before one of them strikes.

Even though I’m a big Star Trek fan, it’s a near certainty that we won’t to be able to colonize other solar systems in the foreseeable future. We night be able to make Mars more Earth-like and livable, but it will take a century or two (if you’re interested in the idea, you can’t do better than to read Kim Stanley Robinson’s Red Mars books). We could also make human colonies in large bubbles orbiting the Earth, in hollowed out asteroids (after we’ve mined out their metals), or in domed cities on the Moon. Rather confining, perhaps, but then how many people now live out their lives without ever leaving a city? Maybe the “upside” of urbanization is that we’re creating a generation of potential colonists. Would people be interested in going somewhere untamed and unpredictable to live? Immigrants have been doing it for centuries.

I was really pleased to follow the exploits of Canadian astronaut Commander Chris Hadfield aboard the International Space Station recently who, through the clever use of Twitter along with impressive photography skills, musicianship, and pure personality, has done more than any man since Neil Armstrong to make space exploration “cool” again. Maybe it’s time for another big push to get people interested in the idea of living somewhere “out there”. If nothing else, mining the Moon and the asteroids and moving as many people as possible to somewhere else might give our planet its one best chance to heal. And the more people go into space, the more they’ll want to go.

At the very least, they’ll gain a gift that existing astronauts always bring home with them: a unique appreciation of the jewel that is Planet Earth.