The dream of visiting Mars is as old as the fantasies of sci-fi authors Edgar Rice Burroughs and Ray Bradbury, but it took a giant step forward in January 2004, when U.S. President George W. Bush announced America's intention of returning to the Moon, and using that as a springboard to the Red Planet.
The proposed U.S. program – still in its early design stages – kicks off with a series of robotic missions to the Moon, followed by more manned lunar missions around 2020. It also involves a new spaceship, called Orion, based on a combination of technology derived from the space shuttles and the venerable Saturn V – the booster used 38 years ago to launch Neil Armstrong, Buzz Aldrin and Michael Collins on their historic voyage to the Moon.
That's the Moon taken care of, but it's yet to be determined when the U.S. program is due to crank it up a notch and set its sights on Mars. With top priority and a liberal budget, it could be done within a decade – or it could take considerably longer before we have astronauts gaping at red-dust sunsets. "I think it's at least 40 years away," says Chris McKay, a planetary scientist with the U.S. space agency NASA's human exploration program at its Ames Research Centre.
Furthermore, there's currently a conspicuous lack of funding. The work is expected to proceed on a piecemeal 'pay as you go' basis, with funds extracted from NASA's normal operating budget, recently running at about US$16.4 billion. Yet nobody knows what a 40-year mission to Mars might cost. Estimates range from tens to hundreds of billions of dollars. To put this in perspective, this is considerably less than the U.S. has spent in Iraq, but is equivalent to 10 to 50 per cent of Australia's annual gross domestic product.
The biggest fear is that the program, ambitious though it is, will get bogged down on the Moon and never make it to Mars. But there are also plenty of other potential obstacles. Right now, we simply don't have the space chops we had 35 years ago, says Scott Hubbard, NASA's one-time Mars tsar, now a professor at Stanford University in California.
To start with, we have to rebuild all that Apollo-era expertise, much of which has been lost as the scientists and astronauts involved have retired or passed on over the years. Space buffs dream that such a program will proceed with the same sense of urgency that characterised the Apollo project after President John F. Kennedy's 1961 pledge to put a man on the Moon by the end of the decade.
But that's unlikely. "A lot of my colleagues want to live in the past," says Hubbard. "That was a Cold War-driven effort, and is unlikely to be seen again unless there is some similar type of national emergency." Or perhaps an unequivocal discovery of life by one of our current robotic probes could give us the shove we need to make the journey to the Red Planet. "That would do it, too," he says.
Such a revelation would also quite likely spark an enormous debate about how we handle the newly discovered life. It's very unlikely the Martian life would have tentacles, bug eyes, or speak Klingon; more likely it would resemble bacteria. But Hubbard predicts the discovery would spark an international scramble over which country leads the mission. Meanwhile, he says, the airwaves would be filled with talking heads endlessly debating what the discovery meant. Had 'incompetent NASA engineers' somehow managed to contaminate our neighbouring planet with Earth life hitchhiking on their probes? Would the Martian bacteria kill us all if it somehow got back to Earth? Or is this simply the proof we've been looking for that we're not alone in the universe? Whatever the outcome, Hubbard's sure of one thing: "humanity would go take a close look – maybe with people in orbit at first and robots on the surface".
