Reports of the demise of ambitious space-science missions at NASA may be somewhat exaggerated.
To be sure, in President Obama's fiscal 2013 budget proposal, two major Mars missions for 2016 and 2018 lost a budgetary wrestling match with the replacement for the Hubble Space Telescope, the James Web Space Telescope.
But Mr. Obama's plan also includes money to begin preliminary studies on a mission to Saturn's moon Enceladus, as well as an orbiter-probe mission to Uranus.
Both represent major “flagship” projects. And the Uranus mission was the planetary-science community's only pick for a flagship mission under a “cost constrained” budget in it's latest 10-year survey, released last year, which outlines the community's research priorities for 2013-2022.
Indeed, with the high-profile exception of Mars, money for the other “cost constrained” priorities – data analysis from existing and past missions as well as money for two other classes of robotic missions in NASA's portfolio – have been targeted for budget increases.
“If you want to set the decadal survey side by side with the NASA budget you're going to find that a lot of the priorities are being pursued,” says Roger Launius, a former NASA historian and now curator of planetary exploration programs at the Smithsonian Institution's Air and Space Museum in Washington.
Spending levels may not be as high as advocates want, he adds, “but it's not as though NASA said, 'We're not doing this. We're not doing that. Go pound sand.' “
However it certainly doesn't feel that way to planetary scientists who focus on Mars.
Although many could see the handwriting on the wall during the past year, seeing the cuts in a final budget proposal hit them hard.
“Everyone realizes it's austere times, that cuts have to be made and growth curtailed” in spending, says Jim Bell, a planetary scientist at Arizona State University who focuses much of his research on Mars' geology. But many people in the science community and at NASA “assumed that the pain would be spread around”– discomfort introduced in no small measure to compensate for cost overruns in both the James Web Space Telescope and the Mars Science Laboratory, currently en route to the red planet.
Initial estimates for the James Web Space Telescope, slated for launch in 2018, hovered around $1 billion in the late 1990s. Current estimates put the cost at $8 billion.
Instead of shared sacrifice, “we're seeing very targeted pain, targeted at the planetary exploration program, and very frustratingly targeted at the most successful part of the planetary exploration program,” the Mars exploration program, he says.
The cuts are all the more frustrating, he and other researchers say, because the latest decadal survey for planetary sciences, which NASA uses as a blueprint for missions, went to great lengths to outline what it saw as a realistic exploration program with modest budget growth as well as scaled-back priorities if budgets truly tightened, as they have.
“We get it,” he says.
This is hardly the first time the planetary-science portion of NASA's budget has taken hits. When President Reagan first moved into the White House in 1981, his budget director David Stockman at one point red-penciled the entire planetary-science line, recalls John Logsdon, professor emeritus and former head of George Washington University's Space Policy Institute.
Other historians note that the fortunes of NASA's space-space science program have waxed and waned over the years.
Even now, “we can do some great things with $1.2 billion,” Arizona State's Bell acknowledges, referring to the budget request for planetary sciences. But the budget for flagship missions to the outer planets has been cut by roughly a third compared with fiscal 2012 estimates, largely because preliminary studies for three different versions of a mission to Jupiter's moon Europa have been completed. The agency wants to focus the remaining money on the new studies for Enceladus and Uranus, as well as on supporting the on-going Cassini mission at Saturn and the development of technologies that would cut the cost of missions to the giant planets.
Even if Congress redistributes money in ways that bolster the Mars program in a final budget, it's not clear that additional money would go toward flagship missions, the most expensive class NASA lofts.
Shelving for now the studies for a flagship mission to Europa and starting with clean scratch pads for Enceladus and Uranus are tough calls to make, acknowledges James Green, who heads the planetary sciences division at NASA headquarters in Washington. But the efforts aren't wasted.
“Even though we're in an austere time, we won't be able to grab new money and start a new flagship, that doesn't mean we're going to give up the dream. As the economy improves, we're going to want to go back and say: Hey, now can we take on the next big event, and it would be a flagship."
Indeed, he says, for a flagship project proposed in a study dropped on his desk only a year ago, NASA would be spending money on a preliminary study at this point anyway, as it has asked to do for Uranus and Enceladus.
As for the Mars program, NASA is launching another orbiter next year. And John Grunsfeld, an astronomer and former shuttle astronaut who recently took over the job as NASA's associate administrator overseeing the agency's science mission directorate, has called for help from the community to think of ways to design future robotic Mars missions in ways that would support eventual human exploration there as well as answer key science questions.
Bell and others note that during the brief heyday of President George W. Bush's Vision for Space Exploration, the Lunar Reconnaissance Orbiter was born to support efforts to return US astronauts to the moon. Launched in June 2009, the craft's first year in orbit centered on mapping the surface, identifying minerals and potential water-ice deposits, and measuring the radiation. Since then, the craft has been taking measurements to answer outstanding science questions about the moon.
During a press briefing on NASA's space-science budget earlier this week, Dr. Grunsfeld noted that given the alignments of Earth and Mars in 2018, that would be a “sweet spot” for another mission to the red planet. “I'm not a betting person, but I would certainly plan on it, because that's what I'm doing here,” he said.