SAN JOSE, California -- It's not hard to sell attendees of the Space 2006 conference on permanent human settlements in space.
Where those settlements should be, however, is another question. Various scientists make their case for Mars, the moon or habitats orbiting the Earth. While the question is not a pressing one for most people, for the futurists mapping the humans path to space, the destination makes all the difference in the world.
For Al Globus, senior research associate for human factors research and technology at NASA Ames Research Center, the most salient issue is one that most people take for granted on Earth: gravity. In low gravity, muscles atrophy and bones loose calcium and become brittle. If people start having children in an off-Earth settlement, those children -- being adapted to the moon's one-sixth gravity or Mars' three-eighths gravity -- may not be able to function on Earth, Globus argues.
"If you are a genius, you can never go to Harvard or Princeton," Globus says. "If you are a great violinist, you will never be able to play the concert halls of Earth."
That's a deal breaker, in Globus' opinion. The space researcher instead argues that rotating space stations that can produce near-Earth gravity would be the best bet for long-term human inhabitants. These stations could produce more energy because certain orbits could bring them more sunshine than is possible if they were land-based. And the stations would be hours away, rather than three days for the moon or, at best, six months for Mars. The proximity to Earth makes tourism a possibility and makes resupplying the stations a snap.
On Thursday, Robert Bigelow, a Las Vegas real estate and financial businessman that started Bigelow Aerospace in 1999, announced that he would put a space station in high orbit by 2012 to spur demand for a destination in space. The Sundancer station, as Bigelow dubs it, would consist of two habitats connected to provide 510 cubic meters of living space, about as much real estate as a small home.
The businessman also underscores that the mantra of real estate still applies: Location, location, location.
"From a business perspective, (Earth orbit) is a revenue-generating location, and from a science standpoint, it's a must," he says.
However, creating a large enough space station to spin for artificial gravity is difficult enough that even the risk-taking businessman is not considering it. His scientists have instead drawn up plans for a module that can be created in space and planted on the moon to become the first part of a base.
The moon has gained adherents as the best initial settlement because the goal is attainable and scientists can use a moon base to study the long-term effects of low-gravity living on humans, said Klaus P. Heiss, executive director of High Frontier, a group of scientists and enthusiasts focused on
creating a moon base.
"The goal should be something that we can do in 10 years with the existing budget, but at the same time, it needs to be significant," Heiss says.
Heiss argues that a long-term moon settlement could develop the lion's share of the techniques necessary to survive for a long time on another planet, such as Mars, a planet with its own supporters. The Mars Society -- whose president, Robert Zubrin, literally wrote the book on the least expensive way to create a Mars base -- has been simulating the working conditions on Mars at
its research station in the Arctic. Another proponent, the
Mars Homestead Project, has created plans for building a base from mainly local resources. Glass, plastics and steel could all be made on Mars and having those resources makes Mars the best location for a long-term settlement, says Bruce Mackenzie, a co-founder of the project.
"Being farther away will help build self-reliance and spur innovation," Mackenzie says.
The distance, at least six months in travel time and two years between trips, should be seen as a plus, he adds, because it minimizes the impact of changes in policies and budget cuts. And with U.S. space policy far from settled, such a distance could be welcome.