A year after MGS reached its final orbit, in March 2000, planetary scientists from all over America and much of the rest of the world gathered in Houston for the Lunar and Planetary Science Conference, just as they have done every year since 1970, when the first such conference pored over studies of the first samples returned from the moon. For a week, the Johnson Space Center’s recreation building was turned over to them, and its basketball courts rang to the announcement of more and more news from Mars. At least a hundred papers on Mars were presented, most of them informed by MGS data in one way or another. To many of those attending, Mars seemed to be changing before their eyes. MGS measurements were discovering new features and forcing the reinterpretation of old ones. The idea that there had once been an ocean on Mars was starting to gain serious respectability. So was the idea that, far from having been geologically dead for billions of years, Mars was in fact still active. The old familiar face of the planet was taking on a youthful cast in the new light. The scientists were as reinvigorated as their planet.
But if the Houston meeting was full of scientific promise, there was also a fair share of institutional foreboding. Condolences were offered to the people who would have been presenting the first data from the Mars Surveyor programme’s 1999 missions, Mars Polar Lander or Mars Climate Orbiter, had it not been for their accidents. Some of these unfortunates – the ones who had worked on an instrument designed to analyse the way the Martian atmosphere changes with altitude – had watched their instrument burn up not once but twice, first on Mars Observer, then again on Mars Climate Orbiter. The reports of a whole slew of investigative committees on the previous year’s disasters were due out in the next few weeks and everyone knew that they would make sad, infuriating reading. While Mars Global Surveyor was a wonder, the programme it had spearheaded was a disaster.
On a phenomenally wet Tuesday evening, on a set of couches in the foyer of a building on the University of Houston’s Clear Lake campus, Carl Pilcher, the man responsible for solar system science at NASA headquarters, discussed the situation with various worried and disaffected scientists. He more or less confirmed that the next Mars lander, one that shared the design of Mars Polar Lander and was due to be sent off in 2001, was being cancelled. He accepted that the constraints that had been put on the programme had proved too tough – that in the effort to force JPL to make the Mars Surveyor programme faster-better-cheaper, mistakes had been made both at the lab and at NASA headquarters. He accepted that faster-better-cheaper had meant that the scientists had worked themselves to the bone and encouraged everyone there to help NASA get it right next time round. When he’d finished it was clear that the Surveyor programme as it had been talked about just a few months ago, with plans for missions in 2003 and 2005 that would not just study Mars in situ but send samples of its surface back to the earth, was over and that as yet there was nothing to replace it. With one exception – a small orbiter that would carry the last of the Mars Observer instruments to their objective in 2001 – the future of Mars exploration was, yet again, a blank.
But Mars itself was not. Just across the aisle from Pilcher’s attempt to share the pain of his bruised community was a special presentation by the MOLA team. As befits a geophysical instrument, MOLA is in the numbers game. If you put enough numbers together, though, you can get a pretty good picture. The MOLA team had taken their data-set, arranged it on a Mercator projection and printed it out as a map. The first version of this map, published in the journal Science the summer before, had been impressive. Garishly colourful, it had shown so much detail in its crater rims and mountain tops that many looking at it had assumed it was a colourful overlay superimposed on some sort of photomosaic or airbrushed map. But every last bit of the picture came from the MOLA data-set, from simple measurements of the time it took for a pulse of laser light to reach the surface of Mars and bounce back to MGS.
By the time of the Houston conference the map had been much improved. MGS had been in its proper orbit for more than an earth year (though only just half of a Mars year, each of which lasts 687 earth days, or 669.6 Mars days). More data had been added and very large printers had been used to blow the image up far beyond the scale of a scientific paper. The version in the University of Houston foyer was about two metres long and a metre and a half high. It would have been eye-catching even if you didn’t know what it was. If you did know, it was little short of a miracle. Here were real data, as hard and scientific as you could wish, woven into the image of a planet. It was not a realistic image. The altitude data were colour coded, so that the terrain ranged from blue in the lowlands through green to yellow to red to white. Hellas, the deep basin in the south, looked out like a baleful violet eye; the rise of Tharsis, its three great volcanoes snowy white, was ringed with burning red. Faint features were enhanced by computer filtering, just as they had been in the Mariner 9 photographs, to exaggerate details. Shaded relief had been added, not by skilled artists, but by a computer program first developed for charts of the ocean floor. It did a pretty impressive job – while still suggesting, as all such shading does, that the planet knew no night and that the sun was somewhere over the north pole. No, the map was not realistic. But to the people who walked by, and stopped, and stared, it was very real.
I watched for an hour or so as almost every scientist with any interest in Mars passing by on the way to or from the poster presentations elsewhere in the building stopped to stare at the MOLA map. They talked to each other; they pointed out features. They got close and squinted, then stepped back to take it all in. They enthused and gestured, and then fell silent and just stared. Peter Smith, designer and operator of Mars Pathfinder’s camera and, in his youth, a photographer with serious artistic ambitions, said it was the most incredible picture he’d ever seen. Baerbel Lucchitta, a striking, stately geologist who has been at the USGS in Flagstaff since the early 1970s, traced her favourite features with a little girl’s grin. When people finally walked away, their eyes and minds full, they couldn’t help but look back over their shoulders to get just one more glimpse. Here was a map that was most definitely being treated as an icon.
And David Smith just stood by his team’s creation and beamed. Other people on the MOLA team have told me that they always expected to put together such a picture of the planet, but Smith says he had had no idea the endless stream of data points would add up to such a striking visual statement. When I’d visited him in his office me year before, when the largest printed version of the map had been about thirty-five centimetres across, we’d looked at the data laid out numerically in vast spreadsheets. Though Smith had been keen to have the biggest possible version of the map printed for me Houston meeting, he’d not actually seen the resultant poster before that Tuesday evening. He was looking at it – and showing it off – for the first time, the joy of it all over his face. Across the aisle from the MOLA map, Carl Pilcher was explaining that an era of exploration that had seemed to be just beginning was coming to an end. But Smith just kept talking and smiling and looking with pride at his map. From time to time he’d touch it, running his hand lightly across the smooth blue of the planet’s northern lowlands. As though he could feel the onset of the higher plains to the south. As though the craters might scratch his fingertips.
300 million kilometres away, an instrument he had argued for and cajoled into being and thought about every day for more than a decade was illuminating the surface of an alien planet ten times every second. And in the rain-soaked Houston suburbs David Smith was stroking the face of Mars, a picture of delight.
* At a conference in Germany in 1990, a frustrated JPL engineer named Donna Shirley told a story about a recently deceased NASA engineer asked by St Peter what he’d achieved with his life, to which the answer was ‘First viewgraph, please …’ Shirley eventually led the Mars Pathfinder team.
* Although a shuttle launch costs a lot of money, those costs are not typically borne by any spacecraft along for the ride, but the cost of a one-off rocket is billed to the mission that it launches.
* This sole-survivor-of-an-imagined-series motif is a common one in the history