By that time, Malin had left his faculty position at Arizona State University and, using money from a 1987 MacArthur Foundation “genius” grant, formed a company near San Diego called Malin Space Science Systems, where he would lead the operation of the camera and the analysis of its images. Visiting Malin in his office, I could hear the complex emotions of what had become a very personal effort. “I think of MOC as my eye,” he told me. “Nothing like this camera has ever flown. I hope it works.” Malin was experiencing the potent mix of apprehension and exhilaration that comes with building instruments for other worlds, and he loved it. “This is incredibly addictive,” he said, as his creation headed for a glowing orange dot in the San Diego evening sky. “I’m on my way to Mars!”
The journey turned out to be longer than anyone anticipated.
In August 1993, just before going into orbit around the planet, Mars Observer fell silent; a review board later concluded that the craft had likely been crippled by a fuel line rupture. After the loss of the $800 million probe, NASA administrator Dan Goldin adopted his “Faster, Better, Cheaper” approach to space missions, among them a new, less expensive Mars orbiter called Mars Global Surveyor. When it headed for Mars in November 1996, Global Surveyor carried the backup hardware for Malin’s lost camera. On September 11, 1997, more than a decade after Malin first proposed it, MOC arrived safely in Martian orbit.
A FEW WEEKS LATER, Malin got a visit from Bruce Murray, who wanted to see what his former student was up to. It had been more than 30 years since Murray and his teammates had endured an eight-hour wait for every one of Mariner 4’s low-resolution pictures, the first close-ups ever taken of the Red Planet. Now several MOC images, each offering a level of detail unimagined in 1965, were streaming from Mars to Malin’s offices every day. For Malin, Murray’s visit was more than just a social call; it was a passing of the torch. “It was incredibly rewarding,” Malin recalled years later. “Bruce was like Obi-Wan and I was Luke Skywalker, and now I was the master.” While Murray and Malin were talking, another image came in, and Malin brought it up on the computer monitor. The image covered part of Tithonium Chasma, a giant rift near the western end of the complex of canyons known as Valles Marineris. It was late afternoon on that part of Mars, and the floor of the canyon was in shadow, but the canyon walls were beautifully lit.
Together, Malin and his former mentor combed the sunlit slopes for detail, until they came to a triangular patch of exposed rock, more than 3,000 feet high, that stopped them in their tracks. Within that bright triangle they could see dozens of dark, closely spaced horizontal lines: layers, more numerous and on a finer scale than anyone had suspected exist. Speaking for both of them, Murray uttered an expletive of surprise. In this one image, MOC seemed to reveal that the upper crust of Mars was not what Mariner 9 and Viking had led everyone to expect: It wasn’t a rubble pile of impact debris, like the moon’s crust. In those layers were hints of an untold Martian history.
Some 17 months later, on March 21, 1999, two images came down—years later Malin could still recite the exact frame numbers—that changed his view of Mars forever. They showed part of the floor of Candor Chasma, one of the Valles Marineris canyons. When he saw them, Malin was speechless with amazement: The canyon floor was covered with eroded mesas of spectacularly layered sedimentary rock.
It was the uniform thickness of the layers, the repetitive sequences of rock types, that was so remarkable; on Earth, these were the kinds of layers produced in standing water. You couldn’t rule out some other process—perhaps the layers were made of dust laid down in an ancient, cyclically varying Martian atmosphere and later cemented into rock—but the more Malin looked at the new images of Candor Chasma, the more certain he felt he was seeing sediments that had been deposited in a lake or shallow sea. MOC was letting him look back on an ancient, watery Mars, and the view was spellbinding.
Nearly every place where MOC photographed Martian bedrock—on the walls of craters and channels, on the slopes of buttes and mesas—it revealed more layers. In the ancient cratered highlands, thought to be the oldest terrains on the planet, MOC showed him that the earliest chapters of Martian history were far more complex than anyone had thought. Throughout the ancient crust, interleaved with giant impact craters, were layers of sedimentary rock. They seemed to say that even as the young planet Mars was pummeled by asteroids and comets,
the battered landscape had been dotted by lakes, sand dunes, and drifts of windblown dust.
By this time, Malin had taken on a partner, a 33-year-old geologist named Ken Edgett, who had gone to grad school at Arizona State, where Malin was one of his professors. In temperament, at least, the two geologists were an unlikely pair; one ASU classmate called Edgett a “huggy bear.” But they shared a passion for Mars, and Malin recognized his younger colleague’s skills as a scientist. By the summer of 1998 Edgett was given the important role of choosing most of the camera’s targets. Each day he combed the planet-wide mosaics of old Viking images for the most important places on which to train MOC’s powerful eye. There was a long list of features, from valley networks to polar layers, that had been known since Mariner and Viking, all of which were ripe targets.