NASA's Mars Curiosity rover uses its mast cam to take a selfie.

WASHINGTON — The process NASA’s Planetary Science Division uses to determine whether operating spacecraft deserve mission extensions is fiscally shortsighted, disjointed and opaque, the agency’s inspector general (IG) wrote in a report released Oct. 9.

The sting is all the greater for the Planetary Science Division — which operates missions such as the nearly 3-year-old Mars Curiosity rover and 17-year-old Cassini Saturn orbiter — considering the inspector general said it found no major issues with the senior review process used in NASA’s Astrophysics, Earth Science and Heliophysics divisions.

All four NASA science divisions are legally required to conduct scientist-led reviews of operating missions every two years, but only the Planetary Science Division exempts missions from review without adequate justification while at the same time requiring reviewers to make funding recommendations for two-year periods instead of five-year periods, as is typical for NASA’s other three science divisions, NASA Inspector General Paul Martin wrote in the report, “The Science Mission Directorate’s Mission Extension Process.” The IG’s audit took just over a year to complete and wrapped up in August, meaning it overlapped with a five-month Planetary Science senior review that concluded in July.

“In our judgment, these shortcomings impair the Planetary Science Division’s ability to inform its budget formulation process and ensure the effectiveness and transparency of its Senior Review process,” the IG wrote.

The watchdog recommended the Planetary Science Division require review panels to recommend at least four-year funding guidelines, which would be easier to fold into the notional five-year budgets included each year in the White House’s annual budget request to Congress, and to review each operating mission at the earliest possible opportunity, rather than exempting missions on a case-by-case business as was done in the last two senior reviews. Whenever the Planetary Science Division wants to excuse a mission from review, it should document the reasons, and obtain a waiver from NASA’s associate administrator for science. The 2012 Planetary Science senior review alone cost $1 million to conduct, so extra reviews should be avoided whenever possible, the IG said.

The IG also recommended the associate administrator develop standardized senior review guidelines for the entire Science Mission Directorate.

John Grunsfeld, the current associate administrator for science, subsequently promised to conduct his own directorate-wide evaluation of the senior review process, to be completed by August. However, he also defended the peculiarities of the Planetary Science Division’s senior review process.

In a letter dated Oct. 7 and appended to the IG’s report, Grunsfeld wrote that he was “concerned that the scientific missions vary enough between divisions that tailored approaches to their senior review processes may be warranted.”

After the latest Planetary Science senior review, the results of which were released in September, NASA concurred with reviewers’ recommendations to extend all seven missions up for consideration. Among those extended are Curiosity and Cassini. Cassini was the only mission approved for a three-year extension; the other six were approved for two-year extensions.

Meanwhile, three operating Planetary Science missions were exempted from the five-month review, which wrapped up in July: the Mercury Surface, Space Environment, Geochemistry and Ranging orbiter that launched in 2004; the protoplanet probe Dawn, which launched in 2007 to explore two of the largest objects in the asteroid belt; and the Mars Atmosphere and Volatile Evolution (MAVEN) probe, which launched in 2013 on a mission to study the red planet’s upper atmosphere.

The IG allowed that “it may have been logical” to spare the Mercury mission from review this year because it is expected to run out of fuel and crash into Mercury in March. The other two spacecraft, however, “will complete their primary missions prior to the next scheduled Senior Review in 2016 and therefore should have been included in the 2014 review.”

NASA, according to the IG, said it excluded Dawn from the 2014 review because the ion-powered spacecraft is still in the middle of its primary mission to explore the planetoids Ceres and Vesta. As for MAVEN, the probe only arrived at Mars on Sept. 21 and is not scheduled to begin its primary science mission until Nov. 2.

NASA prefers to extend missions whenever practical because the cost of gathering data from an existing spacecraft is often cheaper than designing, building and launching another. The Mars rover Opportunity, for example, got its ninth mission extension this year.

In addition, NASA senior review panels are advised to put pressure on missions to trim their operating costs during extended operations, although that seldom seems to happen, the IG found.

Of the 22 missions that moved from primary to extended mission phases between 2005 through 2013, just one saw a funding reduction greater than 33 percent. On the other hand, 10 of those missions received more money after moving into an extended phase than they got during their primary missions, the IG wrote in its report.

Dan Leone is a SpaceNews staff writer, covering NASA, NOAA and a growing number of entrepreneurial space companies. He earned a bachelor’s degree in public communications from the American University in Washington.