Journeying to Mars -- on a One-Way Ticket

* A one-way journey to Mars would significantly cut the cost of human space missions.
* The concept could also give humanity a shot at becoming a multi-planet species.
* The first pioneers would be people past reproductive age, who are better suited to handle the harsh radioactive environment.

Finished having kids? Perhaps it's time to think about moving to Mars.

Scientists Dirk Schulze-Makuch and Paul Davies figure that sending astronauts -- particularly ones past their reproductive years -- on one-way journeys to Mars is the most economical way to pioneer the space frontier and establish humans as a multi-planet species.

"This is not a suicide mission. The astronauts would go to Mars with the intention of staying for the rest of their lives, as trailblazers of a permanent human Mars colony," Schultz-Makuch, with Washington State University, and Davies, at Arizona State, write in this month's Journal of Cosmology.

"Their role would be to establish a base camp to which more colonists would eventually be sent, and to carry out important scientific and technological projects," the scientists wrote.

Because of the harsh radioactive environment in space, the authors propose people in in their mid-50s or 60s would be the right age to go, Schultz-Makuch told Discovery News. The lifestyle would be tough, but the authors figure the space pioneers would have about a decade to work on a settlement.

The mission would begin with robotic ships, stocked with about two year's worth of food, agricultural kits and tools.

The robots' first job would be to get some power flowing, most likely a small nuclear reactor, supplemented with solar energy. A steady stream of freighters would keep the outpost resupplied until it was able to become self-sufficient, Schultz-Makuch added.

The scientists suggest an initial group of four people be sent to Mars, and had no recommendations about gender. "I suppose two men and two women would be good," Schultz-Makuch said.

The plan would cut sharply cut the cost of a human mission to Mars -- the authors estimate not needing fuel and supplies for a return trip to Earth could save about 80 percent -- while paving the way for future colonization.

An outpost on Mars (eventually colonized by younger people) would also be a way to preserve the human species should an asteroid impact or some other disaster wipe out life on Earth, they point out.

"There are many reasons why a human colony on Mars is a desirable goal, scientifically and politically. The strategy of one-way missions brings this goal within technological and financial feasibility," the scientists wrote.

The plan is likely to raise some ethical issues, but the scientists said sending people to live on Mars "would really be little different from the first white settlers of the North American continent, who left Europe with little expectation of return."

The idea is getting some attention at NASA and the Defense Advanced Research Projects Agency, or DARPA, which is collaborating on a study called "The 100-Year Starship" intended to explore how to sustain human spaceflight a century from now.

The study, scheduled to last a year, anticipates a mix of private and government funds will be needed to "ensure continuity of the lengthy technological time horizon needed," writes DARPA in a statement about the project.

Apparently, there are no shortage of volunteers. "I get emails all the time from people wanting to go," Schultz-Makuch said.