Fifty years after President Kennedy’s call to put a man on the moon, the space agency is at a crossroads. NASA is preparing to retire its final shuttle this summer, with no immediate plan to replace the agency’s only human space flight program. Amid so much uncertainty – and soul searching for the agency – NASA scientists still need working plans.

Many of NASA’s science goals come out of 10-year surveys, which are based on submissions from the broader science community and seek to establish consensus on research priorities. “I believe that a decadal timeline was selected because, for many grand challenges in science, a decade is kind of a minimal amount of time you have to look at to begin to derive some kind of answers,” says Elizabeth Cantwell, a National Academies board member, who recently co-chaired such a report for NASA.

Presidential terms, however, span eight years at most, Congress changes every two years, and the budget is up for consideration every year. These faster cycles can strain any long-term government project, but especially science programs that require methodical continuity.

‘Guided by Science’

Did Mars or Venus ever host watery environments that could support life? If so, did life emerge there? How did our largest planets and their satellite systems come together?

These are among the most important questions for NASA’s planetary sciences division to consider throughout the next 10 years, according to a new report on priorities for the planetary sciences, which scientists have been touring the country to discuss this spring. Designed specifically to guide NASA policies and programs, the survey was conducted by the National Research Council, which considered 199 white papers submitted by the scientific community as well as issues raised at more than a dozen scholarly town hall meetings.

“What we do must be first and foremost guided by science,” Steve Squyres, a Cornell University astronomer who chaired the survey, told a planetary science conference in March.

“This is an extraordinary thing,” he said. “It’s an instance where a federal agency looks to its constituents, to our community, for actionable advice on what they ought to do.”

Although the report was based on input from the scientific community, the completed product has to be sold back to those same scientists – the goal of many town hall meetings this spring. Next, the whole package has to be sold to Washington – every year. Squyres asked the scientists at the conference in March, especially those in the districts of lawmakers with appropriations clout, to lobby. “The most important thing that we as a community can try to do is to influence the budget process for the NASA planetary science division,” he said. “That means interacting with our congressmen and our senators.”

Paul Hertz, chief scientist of NASA’s Science Mission Directorate, notes that the science mission doesn’t stand alone. “Of course national priorities get added on to the decadal priorities,” he says, noting that in 2004, President George W. Bush “adopted a new vision for space exploration, which changed the priorities for NASA and the allocation of money, and of course over the last year or two, things have changed a lot.”

Indeed, making long-range plans in a politically shifty environment is no easy task. That point was even more evident in another 10-year study the National Research Council recently conducted for the life and physical sciences research program in NASA’s Exploration Directorate. The program deals with science focused on the properties of space and zero-gravity, including their effects on human health.

Unlike most of the 10-year science studies that NASA and the National Science Foundation request, Congress called for this one, and the National Research Council was asked specifically not to consider costs in determining priorities.

“It was a pretty tall hill to climb to put together an integrated portfolio without considering budget in an environment where policy was changing frequently,” says Cantwell, the survey’s co-chairwoman, who is also director of mission development for engineering at Lawrence Livermore National Laboratory.

Getting There

Laying out priorities for a decade with uncertain prospects for human space travel also was a challenge. The report, starkly titled “Recapturing a Future for Space Exploration,” was written as NASA was winding down its space shuttle program. The last shuttle mission is scheduled to launch at the end of June, bringing to a close three decades of operations and 135 missions. After the shuttle Atlantis returns to Earth, NASA will not for the foreseeable future have a vehicle to carry its astronauts to space.

NASA had been developing vehicles under its Constellation program to support Bush’s vision for post-shuttle space exploration initially to the moon as a stepping stone to Mars. In 2010, President Obama called for the cancellation of Constellation, deeming the program too expensive and too far behind schedule. Legal and political knots held Constellation in limbo for months before it officially closed down this year.

The cancellation was a major shift. More than $13 billion had been spent on Constellation, as of April. (If dollars were years, that would be about the age of the universe.) The program also represented the agency’s nearest-term human space flight plans.

NASA’s 2012 budget calls for money to invest in flight systems that would take humans beyond low-Earth orbit, including a deep space capsule and heavy lift rocket, and research to enable the long journeys. But near-term goals are scant in the budget request. Obama is recommending a slight increase for exploration, but much of it is slated to go toward partnerships with the commercial space industry to get cargo and crew to the international space station – part of the president’s controversial push to privatize more of NASA’s work.

“This budget requires us to live within our means so we can invest in our future,” NASA Administrator Charles Bolden said when the 2012 request was released. “It maintains our commitment to human spaceflight and provides for strong programs to continue the outstanding science, aeronautics research and education needed to win the future.”

Obama insisted last year that he is “100 percent committed to the mission of NASA and its future.” He acknowledged a “sense that folks in Washington – driven less by vision than politics – have for years neglected NASA’s mission and undermined the work of the professionals who fulfill it.” And he observed that NASA’s budget “has risen and fallen with the political winds.”

The exploration study notes that NASA’s life and physical sciences program already was under pressure. In 1996, its budget was about $500 million, but in 2010, it was only $150 million, according to a draft of the report.

“Researchers must have a reasonable level of confidence in the sustainability of research funding if they are expected to direct their laboratories, staff and students on research relevant to space exploration,” the draft says. It stresses the need for a coherent research plan that is given appropriate resources. “This is especially noteworthy in light of the frequent and large postponements that NASA’s exploration-related goals have experienced over the past several decades.”

Whims of Washington

NASA is no stranger to the whims of Washington. The first major shift in policy occurred shortly after President Eisenhower left office.

Historians describe Eisenhower as a reluctant father of the U.S. space agency. The Soviet Union’s successful launch of sputnik in October 1957 forced his hand, and NASA opened for business one year later. Eisenhower was more interested in a robotics-based space program, with a focus on spy satellites, historians say. He allocated the agency only about 0.5 percent of the federal budget – its lowest funding share, until recently.

If sputnik was a driving force in the creation of NASA, cosmonaut Yuri Gagarin likely drove the timing of Kennedy’s moon speech. Gagarin became the first human in space after successfully orbiting Earth in mid-April 1961. A month and a half later, Kennedy asked Congress to fund a project to land a man on the moon “before the end of the decade” – the Apollo program.

“That was the first time when a new administration came in and sharply changed the direction for space policy from a previous administration,” says Howard McCurdy, an American University professor and author of several books about NASA, referring to the fledgling agency’s first presidential transition. “President Kennedy originally contemplated setting the landing-on-the-moon deadline in 1968, to avoid a change of administration.” McCurdy says the end of the decade was chosen with the “general presumption that the next president would not cancel a program so close to its completion.”

Eisenhower continued to believe the mission was a waste of money: “Spending $40 billion in a race for national prestige is nuts,” the former president was quoted saying in a 1963 Popular Science magazine article. Putting a man on the moon actually cost $25.4 billion, according to figures NASA gave Congress in 1973. That’s still no small number, especially at the time. NASA’s budget grew to nearly 4 percent of the entire government budget in the mid-1960s – its all-time high – enabling the space program to put a man on the moon in 1969, within the deadline.

Kennedy actually started to step back from his ambitious plan, reaching out to the Soviets before his assassination. “In a field where the United States and the Soviet Union have a special capacity – in the field of space – there is room for new cooperation, for further joint efforts in the regulation and exploration of space,” he told the United Nations General Assembly in September 1963. “I include among these possibilities a joint expedition to the moon.”

McCurdy questions whether the United States would have made it to the moon by the end of the decade if the president had not been assassinated. “When Kennedy realized how much it would cost to go to the moon, he looked for an exit strategy,” he says.

Nearly every administration has tweaked or outright changed the NASA of its predecessor, and Congress has been quick to throw in its own 2 cents. Obama’s break with Bush on NASA policy was severe, but not without precedent, and the decrease in the NASA budget – as a percentage of the entire federal budget – follows a trend rather than sets a new direction.

Lawrence Livermore’s Cantwell notes the deleterious effect policy shifts can have on science, especially for longer-term programs, such as a Mars mission. “If research starts every few years, when a president is so inclined, and then it ends, it will always be 30 years out,” she says. “Science needs some continuity of thought in order to move forward.”

McCurdy is doubtful of such continuity: “The long-range vision of returning to the moon and going to Mars – that overlaps four or five presidential administrations, providing ample opportunities to delay and change the plan,” he says.

Looking Up

Roger Launius, space history curator at the Air and Space Museum and formerly NASA’s chief historian, is more of an optimist. “I think we set priorities all the time, and they – generally speaking – are maintained over the long haul,” he says, noting that the Apollo mission lasted until NASA scientists determined after six piloted moon landings it was not a sustainable program. The space shuttle program has spanned a remarkable eight presidential administrations, far exceeding its predicted life.

Launius argues that 10-year surveys can help scientists make their case to politicians. “They serve as a rallying point for the community engaged in this stuff to make sure that they don’t twist in the wind when there’s a new Congress or panel in the White House.”

The astronomy division of NASA’s science directorate has been using the surveys for nearly 50 years to prioritize popular and successful projects, such as the Hubble Space Telescope, the Chandra X-ray Observatory and the Spitzer Space Telescope. Other science divisions began using them more recently. The planetary science survey that went on tour this spring, for instance, was the second such report.

NASA’s Hertz says the previous planetary sciences study predicted the priorities in that field that developed during the past 10 years. “Almost everything we did came from the priorities in the decadal survey,” he says.

“From my view, the place where we didn’t do everything within the decadal survey has to do with the things that required more money than we had available,” Hertz says. “But that’s not priorities. Priorities are different than budgets.”

Launius suggests lawmakers have been the thorn for the agency’s productivity:

“Where NASA’s had the most trouble has been when Congress has placed on it certain restrictions that it’s had to adhere to,” he says, such as when lawmakers stipulate money must be spent within a particular year. NASA is generally permitted two years to spend appropriated money, and freedom to spend in unequal sums is important for contracting purposes, according to Launius.

American University’s McCurdy says the problem is in the process. “If we’re looking for solutions, the gremlin in this story is the annual appropriation,” he says. “Congress basically reviews every space program every year.” McCurdy thinks bonds might be a better way to fund NASA.

Launius dismisses existential concerns about NASA. “It is asked to do far too many things with far less money than is required,” he says of the agency, but he notes there is no opposing force in the way there is for other parts of government that do science-based work, such as the Environmental Protection Agency. “Even when there are serious campaigns to do wholesale changes, most of them don’t come to pass,” he says.

Science priorities don’t change very quickly, according to Hertz. “They don’t have anything to do with administrations, or how the economy is doing, or what the budget is, or which party is in power, or when the next election is,” he says. “Now, we as a government agency have to execute a program for the American people. We have to plan on timescales that are shorter than a decade, and so we have to do our planning more frequently.”

After five successful spacewalks that have left the Hubble Space Telescope more capable than ever, astronauts on the space shuttle Atlantis held a space-based press conference today.

(See “Shuttle Crew’s Repairs Will Leave ‘Best Hubble Ever.’”)

The crew recounted the mission’s unexpected obstacles, advocated for human exploration of space, and turned their eyes to new frontiers—before they’d even returned to Earth.

“In human space flight, as much as we love lower-Earth orbit, it’s time to leave lower-Earth orbit and go out and explore the cosmos,” veteran spacewalker John Grunsfeld said.

Hugs for Hubble

Grunsfeld and fellow crew member Andrew Feustel, who was on his first space mission, were the last humans to work directly on the orbiting observatory. No more manned servicing missions are scheduled or likely.

“We both gave Hubble one last hug before coming inside,” Grunsfeld said. “We knew that [crew member Megan McArthur] was going to be the one to hold Hubble the last time and send it on its way.”

Operating a robotic arm from inside the shuttle, McArthur had let go of the satellite on Monday morning, and Atlantis slowly pulled away (see video below).

The mission successfully installed two new science tools, fixed two ailing ones, and replaced batteries and gyrators. But there were definitely hiccups along the way.

For instance, veteran astronaut Michael Massimino struggled to remove the last of 117 screws on one of the science instruments’ handrails during a repair—the screw that had always been the easiest during his practice sessions on Earth, he said.

“What was really most challenging for me was not to give up hope that we could do it,” Massimino said.

Humans vs. Robots

Grunsfeld said such incidents demonstrated “the extreme utility of having people working in space and accomplishing things that are different than what was expected.”

His comments are an indirect response to calls to replace expensive and dangerous manned missions and spacewalks with robotic missions.

“As we push further out, from lower orbit to the moon, Mars, and beyond, we’re going to have to do this kind of work every single day,” he said.

Not before some hard-earned rest, however.

“We’ve been training for this flight for a couple years now,” McArthur said. “We all feel pretty good about what’s been accomplished, but we’re also looking forward to taking a break.”

The seven-member crew is also looking forward to a call this afternoon from U.S. President Barack Obama—and to returning to Earth on Friday, when the predicted weather conditions should provide for a smooth landing.

The fifth and final trip by shuttle astronauts to the Hubble Space Telescope will leave the historic satellite more capable than it has ever been, senior NASA officials said this week.

A shuttle mission scheduled for mid-October is set to deliver new components and undertake extensive in-space repairs—a first—on broken instruments attached to the orbiting observatory.

With the phase out of NASA’s shuttle program, the trip is almost certainly the last chance for astronauts to tweak and improve the telescope that helped scientists determine the age of the universe—13.7 billion years old—and popularized images of deep space.

“If we actually repair the two broken instruments [a camera and spectrograph] , we’ll be in a position of having five fully functional instruments for the first time since launch” 18 years ago, said Edward Weiler, who leads NASA’s science division.

“We’ll have the best Hubble ever, there’s no question,” Weiler told reporters during a Monday briefing at the Goddard Space Flight Center, in Greenbelt, Maryland.

(Related story: Hubble Telescope Turns 15 [2005])

The mission is designed to extend the telescope’s life by five years. But Weiler said the repairs could keep Hubble working for as many as ten.

Hubble Repairs

Launched in 1990, Hubble was built with handles, foot restraints, and other features to allow astronauts to work on the observatory from space.

Even so, previous servicing missions have involved only installations and removals. The plan to repair a broken camera and a spectrograph tool during next month’s space walk is unprecedented, NASA managers said.

The instruments “were not meant to be repaired … the way we’re doing it,” said NASA shuttle astronaut John Grunsfeld, who has visited Hubble twice during five space missions.

At a press conference Tuesday, Grunsfeld joked: “They’re sending me back, because I left a critical tool inside the telescope, and I’m the only one who knows where it is.”

111 Screws

After the shuttle, named Atlantis, meets up with the telescope next month, astronaut Mike Massimino will replace an electronics-board cover on a Hubble spectrograph that broke in 2004.

Spectrographs measure the light and color wavelengths that come from objects, revealing key information, such as the chemical makeup of celestial bodies and their surrounding gases.

The elaborate repair requires Massimino to remove 111 screws with a tool made specifically for the job.

Additional instruments to be installed by NASA astronauts:

— a new spectrograph more sensitive to ultraviolet color bands, which will allow Hubble to more deeply probe the large-scale structure of the universe;

— new gyroscopes and batteries that will keep the satellite powered and correctly aimed.

— a mechanism for a rocket to attach itself to Hubble and safely guide it back to Earth when the telescope is finally decommissioned.

Safety First

Hubble, which now orbits about 350 miles (550 kilometers) above Earth, has not been serviced since 2002.

Safety concerns following the destruction of the shuttle Columbia in 2003 delayed this final servicing mission, which was originally scheduled for 2004, then 2006.

During the upcoming mission, a second space shuttle—Endeavor—will sit on the launch pad, ready to blast into space and aid the seven Atlantis astronauts in the event of an emergency.

After the Columbia disaster, manned missions were required to have mid-space rescue plans. All previous post-Columbia shuttle missions have gone to the International Space Station, which is considered an adequate mid-space safe haven.

But the space station is too far from Hubble to be part of a rescue, making the second standby shuttle mission necessary.