The search for life in the solar system, whether in rocks from Mars or on a Jovian moon, tops the wish list of a panel of space scientists convened by the National Research Council. Mindful of shrinking budgets, the panel has issued hard-nosed recommendations that identify which planetary science missions NASA should fly in the decade beginning 2013. Even some top-rated missions should be either deferred or outright canceled if their estimated costs can’t be significantly cut, the panel says in a report released March 7.
Among its big missions, the panel says, NASA should give highest priority to the Mars Astrobiology Explorer-Cacher. This project would be the first of three missions designed to collect Martian samples and bring them to Earth for analysis of any evidence of life forms. But the panel of space scientists recommends that the mission should go forward only if NASA’s cost can be limited to $2.5 billion — $1 billion less than the project’s estimated price tag in fiscal year 2015 dollars (adjusted for inflation). The European Space Agency and NASA, which will jointly run the mission, should work together to reduce the high cost, the report suggests. One possibility is to include one large robot instead of two.
“I’m ready to hit the ground running with Europe to see if we can do something with that first priority,” says Ed Weiler, NASA’s associate administrator for science in Washington, D.C.
NASA’s Jupiter Europa Orbiter also received a nod from the panel, which ranked the mission as the second-highest priority among large projects. The craft would carry a suite of instruments to determine if Jupiter’s moon Europa has an ocean — a possible haven for life — buried beneath its icy surface, as many scientists suspect. But the panel says the mission should fly only if the project’s current estimated cost of $4.7 billion is reduced and if NASA increases its planetary science budget. The panel did not say specifically how much to cut from the Europa mission in order to maintain funding of other projects, but did spell out a 5 percent boost to NASA’s planetary science research funding compared with FY 2011. The panel also recommends that the planetary science budget should remain 1.5 percent above inflation for the remainder of the decade.
Exploring the structure, composition and atmosphere of Uranus with an orbiter and probe also earned a high mark from the panel, which rated the project third among NASA’s large missions. But the panel recommends the mission be reduced in scope or canceled if it rises above its estimated $2.7 billion cost.
The report also encourages NASA to fund two new midsize missions among five candidates but did not say which to choose. The five possibilities include a Venus lander, a probe that would descend though Saturn’s atmosphere, missions that would sample either the surface of a comet or a large basin at the moon’s southern pole, and a craft that would study the small objects that trail or lead Jupiter in its orbit around the sun. The cap on these missions should be raised slightly, from $1.05 billion including launch costs in FY 2015 dollars to $1.0 billion excluding launch costs, the panel recommends.
Among the least costly missions, the committee recommends that NASA continue to support the ESA/NASA Mars Trace Gas Orbiter, set for launch in 2016, as long as currently negotiated costs and responsibilities between the two space agencies remain unaltered.
The report also urged the National Science Foundation to complete the Large Synoptic Survey Telescope, which will not only probe the nature of dark matter and dark energy but aid in tracking near-Earth asteroids.
Previous reports recommending astrophysics and planetary science missions have been criticized for using cost estimates that were too low. As a result, NASA could not always fund the projects that scientists had pushed for, says planetary scientist Steve Squyres of Cornell University, who chaired the panel. This time both NASA and the National Science Foundation, which cosponsored the report, were specific about keeping recommendations and cost estimates in line with budget realities and requesting fallback options in case funding was less than expected.
“We took the marching orders very seriously,” Squyres said. “We tried very, very hard to be reasonable.”
