Nasa's Curiosity rover is scheduled to land on Mars on August 5. (NASA / JPL / AFP / Getty Images )
NASA and the California Institute of Technology's Jet Propulsion Laboratory face a critical test Sunday night: The spacecraft carrying their latest Mars rover, Curiosity, will execute a perilous seven-minute series of maneuvers after it enters the planet's thin atmosphere at more than 13,000 miles per hour, trying to slow itself enough to drop the rover safely into the deep Gale Crater.
The size of a small car, Curiosity is a 1-ton mobile laboratory designed to collect and analyze samples of Mars' crust as it scales the side of a 3-mile-high mountain. Its fate rests with the ability of the spacecraft's oversized heat shield, parachute and thrusters to brake its hurtling descent. No matter what the craft may encounter, the mission's engineers will not be able to alter its course after it enters Mars' atmosphere. With handicaps like these, it's no surprise that more than two-thirds of the previous Mars landing attempts failed.
As nerve-wracking as that may be — the entire $2.5-billion, eight-year endeavor could come crashing down, literally, during that seven minutes — it's not the only challenge facing the Mars program and the engineers it employs. In the face of recession and hard budget choices, the program is again under pressure from spending-cutters and backers of rival NASA programs, such as climate research. This year, the Obama administration has proposed slashing the funding for Mars exploration by more than $200 million, or almost 40%, effectively putting the program on pause, with no projects in the pipeline after 2014.
INTERACTIVE: Curiosity's journey from liftoff to landing
Even NASA's ardent backers concede that the government has to start tightening its belt, and that giving the agency more money means giving some other program less. But the United States can't afford to risk its technological leadership in space exploration, or squander the gains that could come from firsthand knowledge of Mars.
It's worth noting that the administration proposed to keep NASA's overall budget at about the same level in the coming year as it was in fiscal 2012. But the agency has been plagued by cost overruns inside and out of the Mars program (the Curiosity project is expected to cost 50% more than initially estimated), and it's been forced by Congress to fund projects of uncertain value, such as a massive new rocket that has yet to be assigned a specific destination. The congressional meddling is an irritant, but the cost overruns are like a cancer eating the agency from within.
Complicating matters, NASA's plans for manned space flight have been in flux over the past decades, as the Bush and Obama administrations phased out the space shuttle program and struggled to decide what to do next. The current goal is to put an astronaut on an asteroid by 2025 and on Mars the following decade. That shift in thinking contributed to the break imposed in the robotic missions to Mars; NASA recently convened a panel of in-house experts to help decide what the Mars program should do next, and one of its assignments is to see how those missions might also serve the goals of manned spaceflight.
PHOTOS: Curiosity's date with Mars
Nevertheless, the scientific community has already given NASA clear guidance on what its priorities for Mars should be. In a definitive report issued just last year, the National Research Council said the most important mission in planetary science was to obtain samples from Mars and return them to Earth. That's what NASA and the European Space Agency had been planning to do in 2018, two years after they were due to send an orbiter into Mars' atmosphere to look for signs of past life. The administration's proposed cuts led NASA to withdraw from both of those projects, which the Europeans are expected to continue with a different partner. NASA also worried that the Europeans wouldn't be able to cover their share of the sample-and-return project's $3.5-billion budget.
Having the right mission at the right budget is obviously a requirement for going forward. But it's also important that NASA not sacrifice its leading position in planetary exploration — a position that attracts brainpower, promotes innovation and spurs the private U.S. space industry. Those benefits are on top of the well-documented dividends paid by the taxpayers' investment in the space program, including the development of groundbreaking technologies and the inspiration of generations of new scientists, engineers and adventurers.
The point of exploring Mars in particular is to glean something profound about Earth from the one planet in the solar system that appears to have been formed in a similar way, and whose stable surface has preserved a record of the solar system's history. As the National Research Council put it, "It is now possible to select a site on Mars from which to collect samples that will address the question of whether the planet was ever an abode of life." And if evidence of some preexisting life were found, what happened to the atmosphere that helped to sustain it? Answering that question could provide invaluable lessons for us as we pump more carbon and ozone-destroying chemicals into our air. It would be tragic if NASA came so close to unlocking some of life's great mysteries on the Red Planet, only to drift out of orbit.