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A Scientist's Fight to Send His Camera to Mars on the Mars Global Surveyor - Part III
posted: 07:00 am ET 23 June 2000
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'The time of his life' <-- PREVIOUS PAGE The time of his life The road to the launch pad was long and arduous. "You can't take a day off," Malin recalled. "That might be the margin you needed to make the [launch] window." But scientist Phil Christensen, who was fighting his own battle to perfect his Thermal Emission Spectrometer for the Observer, said Malin enjoyed himself. "He might say, 'oh, it was horrible and it was really nerve-wracking.' But down deep, Mike was having the time of his life. And so was I, for that matter." 
Valles Marineris In 1988, when a belt-tightening NASA decided to prune Mars Observer's payload, Malin and Christensen (whose instrument was another latecomer) feared the worst. To their surprise, the axe fell instead on a sophisticated JPL instrument called VIMS (for Visual Infrared Mapping Spectrometer.) "Phil and I survived," Malin said, "because we were so low-cost that it just didn't make an impact on the budget." At the same time, NASA announced another cost-saving measure, a two-year slip in the launch date from 1990 to 1992. In the interim, Malin's team took some much-needed time to work out bugs in the design. Two big bugs The biggest bug didn't surface until 1991, when the finished camera was shipped to aerospace and technology company TRW in Los Angeles for testing. Subjected to space conditions inside a thermal vacuum chamber, the telescope's graphite-epoxy structure -- touted as rock-stable by subcontractor Perkin-Elmer -- expanded and contracted by minute but unacceptable amounts.  "We survived because we were so low-cost that it just didn't make an impact on the budget."  Even worse, the thin silica primary mirror warped badly enough to ruin the focus. The camera needed a focusing system after all -- and there was little more than a year to go until launch. Once more Soulanille and his teammates came up with an elegant solution: they would take advantage of the mirror's shape-changing tendencies by attaching heaters to the center and the rim of the mirror. By activating different sets of heaters, they could control the mirror's shape, and thus the focus. Converted enemies and a hurricane But something important had changed at JPL: Project Manager Gary Reisdorf, once the camera's most bitter opponent, had been converted into one of its biggest allies. Conscious of the time pressure, Reisdorf fought alongside Malin's team against conservatism and resistance within the lab. By the spring of 1992, with launch only months away, the camera was installed on the Mars Observer spacecraft -- just in time for Malin's team to discover that some parts had been incorrectly assembled. 
Olympus Mons Off came the camera; the mistakes were corrected, and then came another round of testing at TRW, continuing even while the Los Angeles riots raged outside. In June Mars Observer, whole once more, was shipped to Cape Canaveral and rolled to the launch pad atop a Titan 3 booster. Launch was set for mid September. Then Hurricane Andrew ripped through Florida, and on pad 40, within its launch shroud, Mars Observer was contaminated by rain and dust. Once more, the camera was removed for cleaning in a feverish race against the clock; if the spacecraft wasn't ready before the first week of October, when the launch window snapped shut, the mission would be delayed another two years. Onward and upward At last, on September 25, Mars Observer roared skyward and headed for Mars. Even then, Malin could not relax. Would the camera work? Would it focus? Finally, in late January 1993, the first test images were beamed to Earth. They showed nothing more than a few stars, but to Malin those points of light were gorgeous: They were in focus. Sadly, in August, Observer was lost most likely due to an explosion in a fuel line in 1993. But soon there was hope. In standard NASA practice, a "flight spare" of Malin's hard-won camera remained on the ground after the Mars Observer spacecraft was lost. That meant a second chance for the Mars Observer Camera. It was included on Mars Global Surveyor, which lifted off in November 1996. And when the Surveyor slipped into Mars orbit in the summer of 1997, Malin's dream was realized: The pictures started coming in, and with them, a Mars no one had ever seen before.
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