Future Missions Await Review of Mars Failures
(From the March/April 2000 issue of StarDate magazine)
Reports from two independent review boards may determine the fate of the next pair of missions to Mars -- and perhaps the philosophy of the entire Mars Surveyor program.
NASA Administrator Dan Goldin convened the panels to study the failed Mars Climate Orbiter and Mars Polar Lander missions. Climate Orbiter burned up in the Martian atmosphere when a math error sent it too close to the planet's surface as it arrived in September. Flight controllers last heard from Polar Lander just 12 minutes before its scheduled touchdown on December 3. They abandoned their efforts to contact the craft in January. So far, engineers are not sure why the mission failed.
Both missions were part of NASA's ambitious Mars Surveyor program, which was established after the 1993 loss of the $1 billion Mars Observer mission -- the first American mission to Mars since the 1970s. The program was instructed to follow Goldin's "better, faster, cheaper" philosophy of science missions by building large numbers of relatively simple, inexpensive spacecraft designed to meet highly focused scientific objectives.
(The two missions lost last year, plus a pair of probes carried aboard Polar Lander, cost about $365 million.)
Program managers had planned to launch two spacecraft to Mars every 25 months, when Earth and Mars are properly aligned. The first craft, Mars Global Surveyor, arrived at Mars in 1997 and continues to study the planet from orbit. (Soon after Polar Lander was lost, Global Surveyor began photographing the suspected impact site for signs of the craft.)
The next two missions -- another orbiter and lander -- were scheduled for launch early next year. But NASA may postpone or cancel one or both missions if the agency's own audits or the independent review boards find that last year's failures were the result of major managerial or technical problems.
In a preliminary report released in November, the Climate Orbiter review board criticized NASA, the Mars Surveyor office, and the spacecraft builder for failing to evaluate the entire mission as a complete system instead of as a series of individual components. The board also cited inconsistent communications and training and the lack of full verification of the navigation software as contributing factors to the orbiter's loss. The panel continued its work early this year, and a second report will recommend ways to avoid similar losses in the future.
The second panel, the Mars Program Independent Assessment Team, first met in January. It will review both of the failed missions and report to Goldin by mid-March. It will analyze budgets, schedule, management structure, and scientific organization of each mission and recommend changes that could increase the chance of future success.
If NASA allows the next two missions to proceed, the orbiter will launch on March 30, 2001, and enter orbit around Mars seven months later. If successful, its instruments will map the composition of the Martian surface and measure radiation in the space environment around Mars.
The lander is scheduled for launch on April 10, 2001, and touchdown on January 22, 2002. It will carry a small rover almost identical to Sojourner, the rover carried by Mars Pathfinder in 1997. The lander also may test equipment for manufacturing rocket fuel from chemicals in the Martian atmosphere; future manned missions may produce their own fuel on Mars for the return trip to Earth. -- — Damond Benningfield
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