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Planetary News: Mars (2006)Next, the Weather From Mars -- with Dan McCleeseBy A.J.S. Rayl10 Mach 2006
The Mars Reconnaissance Orbiter (MRO), now in orbit at the Red Planet, features six state-of-the-art science instruments to study the planet from the atmosphere all the way down below the surface as part of the most technologically sophisticated payload ever flown to another planet. One of these instruments -- the Mars Climate Sounder (MCS) -- in essence, a Martian weather satellite -- has been to Mars twice before, yet this mission will be its debut. This feature chronicles the story of the little Martian weather satellite and Daniel J. McCleese, the atmospheric physicist who has worked throughout his career to get it in operation at Mars. Of course, McCleese, who also happens to be the Mars Chief Scientist at the Jet Propulsion Laboratory (JPL), didn’t do it alone. An international team of scientists have contributed to the effort over the years, some, including his deputy principal investigator Tim Schofield, hail from the United Kingdom, and others from Russia, and the United States. Like the director of a movie, however, the vision belongs to McCleese. This project was his dream first and he has worked a lifetime to give it life. The third time’s the charm, as the saying goes, and destiny seems to be demanding a different outcome this time around. But whatever the outcome, from this chronicle the “right stuff” emerges – the imagination, the will and drive, belief, determination, and resilience it takes to make a vision out there at another planet real. The story begins in the late 1960s, when America was going to the Moon. In sunny Southern California, however, 16-year-old Daniel J. McCleese, then a junior at Chula Vista High School, was into Mars. When it came time to consider projects for the Greater San Diego Science and Engineering Fair, he teamed with schoolmate Michael Hulfactor to create the Mars Environmental Simulator System (MESS). Basically, the MESS was Mars in a box. “We put together a system that simulated all of the environmental conditions of Mars in that box—lighting, temperature, and pressure,” recalls McCleese. With Moon mania all about, "we were academic rebels," chuckles Hulfactor. The duo collaborated for 2 years, and in their senior year, 1967, the MESS won several engineering and science awards. They had planned to go big. "We were going to perform biology experiments using MESS, hoping to adapt anaerobic bacteria, the kind that would grow in the Antarctic or Arctic, to Martian conditions," remembers Hulfactor, who now advances innovative technologies out of the Silicon Valley. Like many high school plans, however, the collaboration ended with graduation when the two MESS-making chums went their separate ways. McCleese was accepted at Antioch College, aided, he is convinced, by his geeky passion for Plato’s dialogues. A work-study program dropped him at the Lab during those undergraduate years. At JPL, he discovered an interest in atmospheric physics that led him to Oxford University in England for his doctorate. “I wanted to both build hardware to investigate things I was interested in and analyze the data and do the interpretations of the data for better understanding,” he explains.
During the mid-1970s and the build-up to the twin Viking landers, McCleese was on the other side of the Pond, busy working on his doctorate, focused on Earth, and completely missed the Mars mania taking place at home. But once his doctorate was in hand and he returned home to take a job at JPL, Mars peaked his interest again. His timing couldn’t have been worse. It was by now the late 1970s, post-Viking and a time, as hard as it is to believe now, when NASA had absolutely no interest in the Red Planet. “As I began to get more and more interested in Mars, I ran into a very, very strong push-back from NASA, along the lines of – ‘We’ve gone to Mars with Viking. It is a dead planet, no longer very interesting to NASA and we are headed for the outer planets,’” he remembers. This was the time of the soon-to-be legendary Voyager mission and a time when Galileo was gaining steam. “NASA wanted to talk about Cassini and Saturn as a new mission and not Mars.” By 1980, McCleese decided to go for his personal “red ring” (let the others have brass) despite the odds against him. The evolution of the climate of Mars and how the weather changes there today were the things that interested him most scientifically. “I tried very hard to get NASA interested in returning for specific narrow investigations that were opened by Viking and not settled,” he says. “One of those was the role of water in today’s climate and how that might teach us about water in the past climate of Mars. I wanted to understand the hydrological cycle on Mars.” McCleese had been “lucky enough” at JPL to work with Barney Farmer who had an instrument on the Viking orbiter that mapped water in the atmosphere for the first time. “I wanted to try to understand how that water in the atmosphere was exchanging with the surface.” In effect, the Pressure Modulator Infrared Radiometer (PMIRR) was born. A nine-channel limb and nadir scanning atmospheric sounder, the PMIRR would vertically profile atmospheric temperature, dust, water vapor and condensate clouds and to quantify surface radiative balance. “I had an instrument idea to pursue, but I had no mission.” As McCleese talked up his idea, he encountered a group of graduate students and scientists at the University of Colorado that had begun to think about very, very tiny missions on the premise that they ought to be able to build and fly planetary missions, years before the “faster, better, cheaper” strategy landed at NASA. Mars Observer and PMIRR
In 1982, McCleese joined forces with Charlie Barth of the Laboratory for Atmospheric and Space Physics (LASP) at the University of Colorado and began promoting something they called the Mars Water mission. To their good luck and good fortune, NASA started calling for ideas for new missions. “The only ideas the agency expected they would get that would really catch fire were for the outer planets, but we pushed very hard and got some traction for a small mission to Mars to follow up on the water story,” McCleese recounts. By 1984, he had approval to submit a proposal. Meanwhile, several closet Mars geologists got wind of the project and gave it a nod as a great idea, but declared that it had to have geology on it to really capture some of the most interesting things about Mars. “Before too long, the Mars Water mission had turn into a very sophisticated, but still modest-sized mission investigating the geology, atmosphere, and interior of Mars.” It didn’t take long before McCleese and crew gained enthusiastic support from the science community. The mission was blessed with funding and christened Mars Observer. Although the mission had grown in scope, the budget never really grew in kind. Costs incurred and critical musts were all scrutinized and often eliminated. “Developing Mars Observer, it always had this ‘it must be cheap, done by industry, and must be able to find a spacecraft that rolls off an assembly line like an Earth communications satellite,” explains McCleese. While NASA was saying, ‘Okay,’ the agency made it clear that the mission was going to be very highly constrained. “In fact, in the original description of the mission, there was to be no camera because it was thought that cameras make missions expensive. It was a little wacky, but there we are.”
McCleese couldn’t complain. There is no complaining in space exploration. He finally had an instrument and a mission, and now he had a team to put together. He brought Tim Schofield, a scientist he worked with at Oxford, over from England to JPL as his deputy principal investigator. David Paige -- now of UCLA -- had just graduated from Caltech and became a postdoc on the team. The team was coming together and the mission was moving along. Then, in January 1986 Challenger blew up. “Beyond the loss of lives and the orbiter, it meant that we no longer had a clear path to launch this thing,” says McCleese. “In the beginning, we were going to be on a shuttle launch, but Mars Observer was one of the very first science missions pulled out of the sequence of flights that the shuttle had laid out in front of it.” As a result of the Challenger loss, Mars Observer lost 2 years and the costs went through the roof. “At launch we were around $700 million having originally been capped around $250 million.” One thing that happened though as the team got closer and closer to launch is that they began to realize how exciting Mars was. Moreover, adds McCleese, “the community of Mars scientists who had been working on Viking data realized that this payload would really produce new and completely different data than Viking datasets.” Mars Observer became an unexpected darling of the terrestrial planets. The mission finally launched on September 25, 1992, from Cape Canaveral, but Mars Observer suffered early on from “teething problems,” as McCleese puts it, with the propulsion system. “There was a decision to pressurize part of the propulsion system in order to deal with a leak that was perceived. Then as we all know, 3 days before we arrived at the planet, when the spacecraft was fully pressurized and the propulsion system was prepared for Mars Orbit Insertion (MOI), it is believed -- although we never heard from it after it turned away from Earth pointing and communication -- it blew up." It was 8:30 in the morning on a Sunday morning when McCleese got the call from Arden Albee, the project scientist. “We picked ourselves up, but slowly from that disaster,” remembers McCleese. The planetary program had almost always previously built two spacecraft, but that wasn’t done for Mars Observer as a way of doing the mission more cheaply. “That new style meant that we didn’t think we’d get another chance. None of us really believed we would have another chance.” Mars Climate Orbiter and PMIRR2As fate would have it, on April Fool’s Day in 1992, Daniel Goldin assumed the position of NASA Administrator and he promptly initiated a new exploration strategy that called for faster, better, cheaper spacecraft. “He was very interested in finding a demonstration for his faster, better, cheaper concept and JPL suggested the Mars program,” recalls McCleese. “We would get more missions, and the missions would be more focused on science. The launch rate would be high enough to sustain the community that was beginning to atrophy. It was all looking good. The concept appealed to Mr. Goldin partly because we were in a position of spreading the risk over multiple missions. The idea he latched onto is that we would split Mars Observer into three separate missions, and each of the missions would be smaller and better in every way.”
Of course, NASA would decide which of the science instruments would go on which mission and it certainly did not guarantee everybody would get a return ride to the planet. In 1993, the agency staged a competition and suddenly everyone who had started with Mars Observer and had become friends and worked together for 7 years were now competing against one another. “It was a very harrowing part of the process,” remembers McCleese. “I would liken it to having a friend die -- the instrument -- and be told, ‘Maybe if you do things just right it might come back to life, but only one of you can live.’ We had to fight it out.” Five instruments were chosen to go on the first mission that eventually was dubbed Mars Global Surveyor (MGS), including the Mike Malin’s Mars Orbiter Camera (MOC), Phil Christensen’s Thermal Emission Spectrometer (TES), and Mario Acuna’s magnetometer among them. But McCleese and the PMIRR did not make the cut and McCleese was not happy about it. But he stayed in the game and went on to compete with the remaining prime instrument, William Boynton’s Gamma Ray Spectrometer, for a guaranteed berth on the second of the three missions resurrected from the ashes of Mars Observer. “In the second competition, one of the things I tried to do was show that if you flew us, the PMIRR on that next mission, we would bring along with us the first element of the Mars Together Program,” McCleese says. (With ever-shrinking budgets for space science, it has become increasingly clear that planetary exploration can no longer be sustained by one nation alone and must become an international, collaborative effort. Mars Together, an international space exploration program, is an example of such an effort.) As it turned out, he did land that berth on the second mission, subsequently named the Mars Climate Orbiter (MCO). “It was obviously focused on what I wanted to do, so it looked a lot more like the original water mission, which I was very pleased about,” he says. Boynton and the Gamma Ray Spectrometer, by default, flew on the final of the three missions, what became 2001 Mars Odyssey.
Once MGS arrived safely at Mars in 1997, it served as the demonstration that faster, better, cheaper worked. “All of the instruments had to be rebuilt but that was okay, because it was still a relatively cheap mission, because there was a lot of hardware left over from Mars Observer,” explains McCleese. MGS, which is still in orbit around Mars today, became perhaps the most successful Mars mission until, arguably, the Mars Exploration Rovers (MER). Importantly, says McCleese, “MGS opened our eyes to a new world.” Back on Earth, McCleese and colleagues got started on the Mars Climate Orbiter mission. “We decided to build an identical copy of the instrument we lost on Mars Observer, so we rebuilt the pressure modulator infrared radiometer for the Mars Climate Orbiter (MCO). As part of Mars Together, we brought a dozen scientists from Russia into the project, and a team led by Vasily Moroz (IKI/Russia) built hardware for the second PMIRR instrument according to the blueprints.” Along with the MCO came a new lander mission that David Paige -- from the original PMIRR group -- proposed to study the terrain in Mars’ north polar regions. “We launched about 3 months apart,” recalls McCleese. “We went first. We had a very short development phase. We had a very lean team. The intensive work that had usually been done by 5 to 15 individuals at the time was being dealt with by one person and a supervisor. The navigation guy had not done a mission before. With the faster-better-cheaper mode, everything we did was done at a minimum -- minimum cost and minimum time. The people who were working at Lockheed Martin who built that spacecraft and us here at JPL did not communicate well -- this was the famous metric versus English units error -- and we plowed into the planet. Three months later we lost Paige’s Polar Lander.” A pall fell over JPL and the joke around NASA still echoes through the halls of the various centers: faster, better, cheaper -- pick two. “We were now a team that was the bad luck team,” sighs McCleese. “We as a team had lost our instrument again.” They weren’t shunned. But they had suffered the worst agony of defeat -- twice. Life, as it turned out, helped McCleese keep it all in perspective. Mars Reconnaissance Orbiter and the MCS
With the birth of each Martian weather satellite in his career came the birth of a child in his personal life and when things didn’t go well at the office he and his wife, Judy, turned the negative energy into positive energy toward family. “During the development of the second instrument, my son was diagnosed with a serious disease and so I turned my sense of loss and frustration with the PMIRR toward the question of how to help get my son well,” explains McCleese. “It was during this period that things began to turn around for him. He’s doing well now and has earned a degree in physics from Occidental College. In turning our energies to try and make something happen to him, I was able to put the loss of the second orbiter in a context of what is really important in life. I have also been lucky enough to be surrounded by people who understood that failure was part of exploration and life I suppose.” Seeing the “fight” and determination in his son made McCleese realize that the apple hadn’t fallen too far from the tree. “I have to admit that I was as determined to fly again after the second loss as I was with the first,” he says. Besides, he and his deputy principal investigator Tim Schofield had already agreed to give it another go. “We wouldn’t re-fly PMIRR again. Its size and complexity made that a non-starter. We would never get it built again and the technology was so old that we couldn’t build it. So Tim set about redesigning the instrument into a smaller, more sophisticated package we called the Mars Climate Sounder (MCS).” So what is it about the weather on Mars that McCleese finds so compelling? “Mars is a dynamic planet today,” he says. “Most of the features we see on the surface have been the way they are for a very long while, but the climate continues to change, the weather continues to change. When we think about how our atmosphere on Earth behaves, perhaps the most alien aspect of Mars is the dust in the atmosphere. Martian dust actually drives the way in which the atmosphere behaves – its circulation, the dynamical changes, the way it behaves seasonally. And dust is actually raised by high winds at the surface of Mars and while most often small storms develop and die away, there are times, particularly during a southern spring when dust storms can evolve and become global and entirely cover the planet, reducing the sunlight that falls onto the surface of Mars by as much as 80%.”
Down the space highway, when human crews travel to Mars, knowing which way the wind blows on Mars and when, where, and how big those swirling dust storms are going to be could mean the difference between life and death. “When humans land on the surface of Mars, which I think will eventually happen, they will care about the characteristics of the Martian weather, the dust and intense cold on the surface, and will really care if the weather’s going to go south on them when they’re out trudging around in their suits or running machinery,” McCleese says. “There are things in the Martian atmosphere can get you.” The dust storms on Mars are weather events that humankind has been observing intensely since telescopic observation began on Earth. During the last decade, however, Mars missions have been collecting a record of dust, says McCleese. “What’s interesting with the MGS TES data is that over three Mars years (six Earth years) Mars has behaved very differently year to year, so differently in fact that the atmosphere and the way it behaves from the surface all the way up to high altitudes is quite different. We wonder if what we’re observing is a natural variability of the atmosphere of Mars or if we are seeing the process of further climate change and we designed the Mars Climate Sounder to focus on this question in our effort to observe and better understand that climate and weather on Mars.”
Chance, as the old adage goes, favors the prepared mind, and it wasn’t long before chance presented itself again. When NASA issued its next request for new mission proposals, McCleese and Schofield responded. This competition was between an orbiter and, as it turned out, the Mars Exploration Rovers. McCleese, as JPL’s Chief Scientist of the Mars Program, sat on the committee to make that decision. He voted for MER with MRO to follow. Now, at long last, McCleese’s ship is coming in. The mission objective of the Mars Climate Sounder is to profile the atmosphere of Mars by detecting and measuring vertical variation in temperature, dust, and water vapor concentration in the Martian atmosphere with high resolution and full global coverage over at least one full seasonal cycle or 2 Earth years. The data will be analyzed using computer models of the Martian climate, developed in collaboration between Oxford University and Laboratoire de Meteorologie Dynamique (LMD) in Paris during the last couple of decades. Using similar methods to those used in monitoring meteorology on Earth, scientists will actually feed the MCS data into the models, to produce diagnostics and even estimate future conditions on Mars. In the end, the results will offer a much more detailed picture of the weather systems on Mars, especially the characteristics of the dust storms, all of which will be critical information for future missions. “MCS observes the atmosphere to better understand dust but also to characterize the weather and climate on Mars,” says McCleese. “It does so by observing the edge or as we call it the limb of the atmosphere. You can think of these observations like weather balloons on Earth rising thought the atmosphere and collecting information about temperature water clouds as they rise. But we do the same thing from about 1,000 kilometers distance and never touch the atmosphere. The instrument also scans down to the surface to make observations and in so doing, over a period of one Mars year, in following the ‘follow the water’ theme -- we will characterize some of the aspects of Mars that now cause water to be transported around the planet. We’re trying to look at this water to try and extrapolate back in time to see how water might have formed and moved on Mars many, many years ago and at the same time contribute a beginning to the process of developing enough understanding of the Martian weather system to be able to predict it.” A lifetime has passed since McCleese put the final touches on his Science Fair MESS and it’s been nearly 20 years since he first conceived of trying to put a weather satellite at Mars. His children are grown. Team members have come and gone. Happily, Conway B. Leovy, who gained renown for his work on the atmospheric studies from Viking, will be emerging from retirement to join the MCS team. Some, however, have passed on. IKI’s Moroz passed away between the second and third instrument development efforts, and a young investigator, Bob Haskins, who had been instrumental in data analysis preparation also passed away. Now it is the future – and it’s not about viewgraphs anymore. America is preparing to go to the Moon again and McCleese, now an aging Baby Boomer, has done his best to put the aura of his little weather satellite around Mars for real.
Through it all, McCleese’s determination has stayed strong. Those who ask why probably may never be able to understand what motivates explorers. “The feeling about the exploration objective that I think drives us all is that it isn’t about one instrument or two instruments or three, it’s the doing of it and the pursuit of scientific objectives -- that’s what it’s about,” says McCleese. “Each step is then part of a path where, whether you succeed or fail, there is something that follows, and until we get the data from this particular investigation, I think we can’t take that next step.” McCleese pauses, as if rewinding through the memories of all the moments, the work, the losses, and that science fair so long ago. “Mars seemed to me to be a place that was ours – accessible. It never lived in the realm of science fiction for me. It just seemed so logical that we would first go to the Moon, and then our robotics would go to Mars, and then eventually humans would to Mars.” If everything goes as designed with MRO and the MCS in coming weeks and months, Dan McCleese will come full circle in a way no previous space explorer ever has. With MRO safely slowing into orbit on March 10, all indications are that he's on his way to at long last completing that orbit. Click here to visit the Mars Climate Sounder website |
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