The rover, called Mars Science Laboratory, or MSL, and nicknamed Curiosity, has already seen several launch delays and last-minute infusions of funds. But unresolved technical issues, incomplete software and chronic underestimation of costs may push the price tag up by another $44 million.
“Based on our calculations, unless managers request additional money the Project may have insufficient funds to complete all currently identified tasks prior to launch and may therefore be forced to reduce capabilities, delay the launch for two years, or cancel the mission,” wrote NASA Inspector General Paul Martin in the report.
MSL is “the most technologically challenging interplanetary rover ever designed,” Martin wrote. It’s four times as heavy as its predecessors, Spirit and Opportunity, and is designed to drive longer distances over rougher terrain and use more than twice as many scientific instruments to search of signs of past or present Martian life.
The rover will also use a new radioactive power system and a nail-biting “sky-crane” system that essentially lowers the rover on a rope from a hovercraft for landing.
MSL is currently scheduled to launch between Nov. 25 and Dec. 18, but that launch date is already later than planned. The rover was originally scheduled to launch in late 2009, but was delayed because several key instruments and other rover components were delivered late. The setback pushed development costs up by 86 percent, from $969 million to the current $1.8 billion, and total mission cost up 56 percent from $1.6 billion to $2.5 billion.
Because Earth and Mars only line up once every two years, NASA would have to wait until 2013 if it doesn’t make the launch window this fall, a delay that would cost another $570 million.
As of March, MSL was making good progress toward making that November launch window, the report found. Most of the technical issues that caused the 2009 delay have been taken care of, and the rover is nearly completely built and on schedule to ship from NASA’s Jet Propulsion Lab in Pasadena, California, to the Kennedy Space Center in Florida on June 22.
But three key issues remain. The rover’s on-board chemistry lab, which will collect and analyze rock and soil samples right where the rover sits on Mars, still has problems with contaminating samples, the report found. The sample-analysis system was delivered late in the first place and was one of the main reasons for the 2009 delay. The project managers said they have a way to filter out Earthly contamination through data processing, but the auditors remain concerned that the fix won’t be complete in time for launch.
Two software systems, one for flight and one for safety nets that allow buggy systems to run at lower levels rather than fail completely, are still works in progress. In addition, more than 1,200 reports of problems and failures were still unresolved as of February.
That number is “a little bit on the high side, but not completely out of family with what we’ve seen before,” David Lavery, MSL’s program executive at NASA headquarters, told reporters in a news conference Wednesday. Lavery added that all the software necessary to launch the rover is on track to be ready for November.
Some of the software for operating the rover once it reaches Mars will be put on the back burner and completed on the way. That’s not ideal, he says, but it’s not unusual either — some of Spirit and Opportunity’s software was finished en route, too.
Because of the rover’s complexity and the way problems tend to crop up at the last minute, the report says, the auditors are concerned that there won’t be time to get everything in perfect working order before Nov. 25. Every mission has a buffer of “margin days” built into the schedule just in case, but MSL’s margin shrank from 185 days in 2009 to just 60 days when the report was finished.
And because of historical patterns of cost increases, the report fears that MSL might need still more money before it’s ready to go. The project got a fresh injection of $71 million in December 2010 to complete development, and may need another $44 million more than the last estimate, according to the report.
To put these numbers in perspective, Spirit and Opportunity cost $820 million to build, launch, land and operate for their initial 90-day mission, and more than $100 million more for their years of extended missions. NASA’s Science Mission Directorate requested $1.48 billion for planetary science in the fiscal year 2011 budget.
Associate administrator for the Science Mission Directorate Ed Weiler agreed with the report’s recommendations and reassured the review board that the current budget, plus a $22 million cushion in directorate-held reserves, should be enough to complete the mission. The $44 million the report calls for is already on reserve and included in the overall $2.5 billion price tag, Lavery said.
The problems in the report were “consistent with the sort of thing you would find with a large complex project at this stage of development,” he said. “At this point in time we are completely on schedule for November or December launch.”
Still, we’re uncomfortably reminded of a nervous joke among Mars exploration scientists: “On time, on budget, on Mars: Pick two.”
Source WIRED
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