Because it's there.
That's how adventurers often explain their efforts to scale the pinnacles or explore uncharted territory.
It may also be one reason for America's expedition into the "final frontier, "including the current mission to Mars. But it's certainly not the only one. Today, perhaps more than ever, the US space program is bringing innovation and improved quality of life to people here on Earth.
"Just look at the number of communication satellites being launched.... You can't imagine not having weather satellites," says Edward Stone, director of NASA's Jet Propulsion Laboratory here, which spearheaded the successful Mars probe. "NASA's role, and JPL's part in NASA's role, is to continue to press the physical frontiers, the knowledge frontiers, the technology frontiers.... Our job is to continue to create these new opportunities so they in fact become part of the capabilities of the nation. That's what the government investment is all about."
Even for people who remain unmoved by the thought of boldly sending rovers where no rover has gone before, benefits of the space program are legion. Some appear as individual products, such as hand-held receivers that allow hikers to pick their way through the woods without a compass or automobile drivers to keep from getting lost. (JPL scientists helped refine the receivers behind these devices to track spacecraft.)
Other advances represent "enabling" technologies, such as the digital imaging responsible for the breathtaking images of the Marscape that Mars Pathfinder has sent back to Earth. "We had to develop digital imaging in 1964 because there was no other way to get images back from the planets," says Dr. Stone, who has been at JPL about 25 years. Now "it's everywhere, and in a couple of years it's going to be in your living room" as high-definition television.
In all likelihood, innovations from JPL will keep coming. The lab, a sprawling campus in the foothills of the San Gabriel Mountains, has become the lead example of NASA's "faster, cheaper, better" philosophy.
Stone explains that budget constraints are only one reason for this approach. The other desire is to answer the many questions raised by past missions. "We went to Mars in 1976 and have not been back in 20 years, but if you want to understand another planet, you have to go more than one place. You can't imagine understanding Earth if you'd landed only in one place. But you can't afford to land very many places if it costs you a billion dollars each time you go. The challenge, even from a scientific point of view, is how do you go back every time you can? You have to reduce the cost not by a factor of 2 but by a factor of 10 or 20 in order to be able to go back every two years rather than every 20 years."
Mission costs fall, he adds, as designers demand and engineers deliver smaller, lighter, more-capable equipment, such as sensors, cameras, onboard computers, and communications gear.
Basking in the red glow of fresh images from Mars, the JPL team is rebuilding not only its sense of purpose but also its esprit de corps. With the help of a few self-described "scarred veterans," the lab's young Turks have scored a major success with Mars Pathfinder. Galileo's mission to Jupiter and the coming Cassini mission to Saturn have also put the spring back into the steps of the graybeards.
The current atmosphere represents a turnaround from the dark years just a decade ago, when the space program was in shambles following the loss of the space shuttle Challenger.
Now, almost everyone here sports a pin, decal, patch, or T-shirt advertising a new American space-exploration project - even if it hasn't cleared the drawing boards yet. Former JPL engineers, some of whom came out of retirement to pitch in on Mars Pathfinder, are noticing the change as well. "Some of the retirees have said, 'Gee, you know, it sounds just like the '60s all over again,' " Stone says.