The human colonization of Mars has been bouncing around science fiction and even legitimate scientific discussion for decades. But it's typically been proposed with the assumption that Mars would expand humanity's foothold rather than become an entirely new start. But that's just about what astronomy professors Dirk Schulze-Makuch and Paul Davies propose in a stone-serious paper for the Journal of Cosmology, "To Boldly Go: A One-Way Human Mission to Mars." And they're not talking about the distant future--they see this happening relatively soon, and say they propose the "one-way" mission mostly as a way to get around the financial costs that they say keep us from colonizing Mars right now.

One approach could be to send four astronauts initially, two on each of two space craft, each with a lander and sufficient supplies, to stake a single outpost on Mars. A one-way human mission to Mars would not be a fixed duration project as in the Apollo program, but the first step in establishing a permanent human presence on the planet. The astronauts would be re-supplied on a periodic basis from Earth with basic necessities, but otherwise would be expected to become increasingly proficient at harvesting and utilizing resources available on Mars. Eventually the outpost would reach self-sufficiency, and then it could serve as a hub for a greatly expanded colonization program.
It's not clear exactly what these four intrepid spirits are supposed to do once they get to Mars, which the Mars Rover confirmed is totally devoid of even the most basic grocery stores, not to mention other essentials such as shelter or oxygen. The authors suggest they "eventually develop some 'home grown' industry such as food production and mineral/chemical processing." Demonstrating a somewhat hazy understanding of multinational politics, the authors suggest that a "permanent multicultural and multinational human presence on another world would have major beneficial political and social implications for Earth." Just like the United Nations?

It's unclear whether Schulze-Makuch and Davies plan on having the first batch of four colonists reproduce, as they will "endure some radiation damage to their reproductive organs" during the trip. However, after "several decades," they foresee about 150 colonists, all living underground to protect from the sun's radioactive rays, "which would constitute a viable gene pool to allow the possibility of a successful long-term reproduction program."

The authors also suggest colonizing asteroids.