Mars Exploration Rovers Update: NASA/JPL Team Celebrates Rovers' First Year on Mars as Spirit and Opportunity Return
Posted by A.J.S. Rayl
05-01-2005 11:00 CST
As Spirit rang in her new year at Gusev Crater on Mars Monday, NASA officials and mission team members celebrated the Mars Exploration Rovers first anniversary at an event that featured a press conference, storytelling session, and birthday party at the Jet Propulsion Laboratory (JPL).
"What a year it was," Charles Elachi, director of JPL and NASA Advanced Planning, mused before the hundreds of people who packed into Von Karman Auditorium to remember and 'relive' Spirit's landing.
Spirit has begun her second year on Mars investigating rocks unlike any ever seen before on Mars. Her twin, Opportunity, which landed 20 days later on the other side of the planet, officially completes her first year January 23. The rovers are funded through March, but there are no indications right now they'll be ready to stop then.
At an initial cost of about $820 million, the twin robot field geologists -- which were designed and built and are being managed out of JPL -- were guaranteed to last 90 days. Now, one year later, they're tolerating a few mechanical aches and pains -- Spirit has to drive backward as much as forward because of a gimpy right front wheel -- but all in all they are going strong. Each rover is now into her third mission extension and is returning small bounties of science data about our closest neighbor every week, at a combined cost of $3 million per month.
Dozens of team members and a small cadre of global media personnel watched as Elachi lit a candle on a special rover birthday cake, and invited departing NASA Administrator Sean O'Keefe to blow it out. Far less media personnel were on hand than last year and the mood overall was subdued as people whispered about the latest tolls in the tsunami disaster commanding the global headlines. Still, nothing could diminish the accomplishments of these two roving robots. In fact, the robots actually seemed to offer up a little hope for the world, just as they did last year, and even the events of the day seemed to illustrate that. As O'Keefe blew out the candle and began talking, the candle relit, courtesy of the MER pranksters. As the laughs subsided, the administrator continued with his talk, and the candle continued to burn basically unnoticed, almost defiantly until eventually it ran out of energy on the surface . . . an omen, perhaps, of how the rovers will go into that good Martian night?
The MER mission has had all the ups and downs, all the drama and comedy, mystery, dilemmas, and conflict needed for any great epic that crescendos with a happy Hollywood ending -- and it's been quite a ride.
Spirit and Opportunity and their team made it look easy to the world outside, but MER scientists and engineers, and NASA officials, told another story Monday during the press conference and storytelling event, both of which were broadcast live on NASA Television, as they 'relived' what was really going on behind the scenes and the stress they endured to what became the best of all possible endings. Those who were fortunate enough to have been there, journalists included, know well just how different the vibe in Von Karman Auditorium was only one year ago.
"The months leading up to launch were incredibly hectic." Rob Manning, the head of the Entry, Descent, and Landing team, set the stage in a pre-recorded video Elachi introduced at the beginning of the press conference. "We had so much to do and so little time to get it done . . . somehow we managed to get it done before launch. Even then the surprises weren't over. We had the worst solar flare reported in human history hit our vehicle and just days before landing on and Mars had a global dust storm that threatened both Spirit and Opportunity."
Then, one week before Spirit is to descend into the Martian atmosphere, the U.K.'s Beagle 2 lander -- dispatched by the European Space Agency's Mars Express -- was lost. It reminded everyone of the cold, harsh reality that nearly 2 of every 3 missions that dare invade Martian space don't make it, and NASA officials prepared the global media for the worst from the "death planet." The MERs had the benefit of better testing and telemetry technology, and this team believed in its charges and they believed in themselves.
Even so, Manning at one point shared with the crowd gathered in the auditorium, that having to live in a two-face world -- outwardly projecting the dismal realities of travel to Mars while at the same time smilingly, encouraging the team internally to believe and soldier onward -- was quite the challenge. It was all coming together though it seemed -- and then the Red Planet presented Spirit with a different atmospheric profile that the team expected. Individual stress meters registered as high as humanly capable and the tension at JPL was intense as it's ever been.
Someone apparently forgot to inform Spirit of that though. The rover soared through the alien atmosphere, releasing her parachute as commanded, just a bit early, and slowed as programmed from 12,000 miles per hour to zero in about 6 minutes, hitting the surface well-protected by airbags, and bouncing safely to an upright landing (and probably beaming bolt to bolt). Within a week, Spirit was preparing to rove, all systems seemed to be nominal and the team was breathing easier. Until -- Opportunity was on final approach to Mars. Suddenly, Spirit suddenly clammed up and the team was "very concerned" that the communications breakdown "could be possibly very serious," then project manager Pete Theisinger recalled.
"In fact, it was the morning of Opportunity landing that we found out that Spirit was going to survive the software problems it had been plaguing it the last week," Manning remembered. The best of Tinsel Town's scriptwriters couldn't produce drama any better than this.
An agonizing few hours later . . . ecstasy. A double-header. The MER team had two rovers safe and sound and ready to go to work on the surface of Mars. It was, simply, spectacular.
"Then we got those first pictures from Meridiani and it was like nothing anybody had ever seen," remembered Steve Squyres, of Cornell University, principal investigator for the rovers' science payloads. "It showed unambiguously layered -- layered -- bedrock. The thing that we were hoping, praying that after hundreds of meters of driving, maybe we'd find -- maybe -- Bang! It's just a few meters in front of us."
If there was one moment, Squyres added later, from behind the dais in the auditorium, that was it -- "not just because it meant we had two safe vehicles on Mars. But that moment when we opened our eyes and saw that layered bedrock 8 meters in front of us -- man, that was magic."
Jim Erickson, rover project manager at JPL, agreed, and so, no doubt, would most everyone who was there at JPL watching exactly one year ago, for there was history being made in that magic.
"It's been almost a year since I sat right here and said that if things went well we were all about to embark on what was going to be arguably the coolest geology field trip in human history," reflected Squyres Monday. "I think the events have born that out."
Indeed. Spirit and Opportunity successfully achieved their prime directive last March, finding, as it turned out, that both Gusev Crater and Meridiani Planum boasted watery environments millennia ago. Not only had they hit pay dirt, they returned 'the gold' within the primary phase or first 90-days of their journey. Although the water at Gusev seems to have been underground, at Meridiani the evidence points to a salty sea that covered much of the surface at times. Suddenly, the notion of Martian life was real.
Opportunity uncovered in that bedrock before her clear evidence that rocks around her landing area had been deposited in flowing liquid water on the surface of Mars, and the announcement was a moment that will go down in the annals of science history. This is the first in situ evidence -- data collected at Mars -- that shows well beyond a reasonable doubt that the Red Planet once had an environment that could have supported life.
While space agency officials used the occasion to view MER in the context of the multiple successes last year, including Cassini and even Genesis, which managed to return good research even though it crash-landed, there could be no underestimating the rovers' impact on space exploration last year. "What the exploration team had done in the last 12 months is nothing short of remarkable. The ongoing missions of the MERs are simply incredible," noted O'Keefe, who is leaving his position as administrator soon for the post of chancellor of Louisiana State University. "When we finally got the signal that Spirit had safely landed in the Gusev Crater, the joyful celebration here did so much to lift the spirit of our citizens around this great country, as well as around the globe . . . it was a huge, huge event. Most importantly, it gave a boost to all of us at NASA, at a time when we really needed it most."
Many NASA employees and many citizens were still reeling from the loss of the space shuttle Columbia and her crew of seven astronauts in February 2002, and the rovers were medicine for melancholy to be sure. "[MER] was an accomplishment that positively reassured us that we are and continue to do great things and are an extraordinary agency for all those purposes," said O'Keefe, who actually inherited both the 'culture' that led to the loss of the Columbia and her crew, as well as the team who put the rovers on Mars when he took over the administrative reins of the space agency three years ago.
Recalling that he and the team had toasted with champagne at the press conferences following the landings, something that apparently makes government lawyers very nervous, O'Keefe let on that the two empty bottles are currently on display in his office. "I'm as proud of [those] as a lot of the other mementos around the office, and as a matter of fact maybe more so because it was one of the most fulfilling days I have ever had in public service. It was an extraordinary experience. Spirit's successful landing as well as the fantastic work of the orbiting MGS help the set table for President Bush's confident announcement 11 days later on a bold vision for human and robotic exploration throughout the solar system. [MER] was a perfect precursor opportunity for exactly that, and we never planned it that way."
For the MER team -- working on alternating shifts and living on Mars time -- the stress experienced at the landings have continued through operations. "Spirit started out shortly after landing with the file management system anomaly," Erickson recalled. "And then we've had the challenge of going over two and a half kilometers up to the Columbia Hills. We went up to Bonneville Crater and then made the big drive to the West Spur of the Columbia Hills. Opportunity started us off with its own problem: a shoulder joint heater on the instrument arm was stuck on. We quickly learned how to work around it, but then it gave us the opportunity to practice driving on the steep, steep slopes inside Endurance Crater. That was a challenge in and of itself that we weren't really prepared for."
Spirit and Opportunity trekked onward, troopers through it all, and they are roving now, working right through the accolades, the memories, and the celebrations being held down on Earth. Spirit is carrying on with her explorations of the Columbia Hills within the Gusev Crater, climbing up Cumberland Ridge to a crest called Larry's Lookout on the way to the top of Husband Hill. "In December, we discovered a completely new type of rock in Columbia Hills, unlike anything seen before on Mars," informed Squyres.
At Meridiani Planum, Opportunity is checking out the heat shield, which she jettisoned on her entry and wound up breaking into two pieces as it hit the ground. The study could reveal something to engineers about robustness of their designs. Rover team members hope to determine, for example, how deeply the atmospheric friction charred the protective layer. "Both pieces of the wreckage have great opportunities for close-up operations and should be able to tell us a great deal about how well it survived the impact with the atmosphere and maybe the impact with the surface," explained Erickson. "With luck, our observations could give us great opportunities to improve the chances for future missions when they enter the Martian atmosphere or any other planetary atmosphere."
The plan for now is to drive the rovers "as hard as possible until they break down," Squyres offered. Despite the $3 million a month cost, the rovers probably will probably have the chance to shop for rocks 'til they drop. "It seems inconceivable to me that if the rovers are still producing good science that we will not find a way to keep them going," said Firouz Naderi, manager of NASA's Mars Exploration Program, at JPL. "We will manage somehow."
How long could they go, theoretically? No one really knows and no one right now is betting much on when exactly either rover will break down, because the twin robot field geologists continue to astound even their designers with how well they continue operating. "The rovers are in great shape for their age right now," reported Erickson. "They are continuing to set records. Spirit has driven more than 4 kilometers (2.5 miles] and Opportunity has completed 2 kilometers. Together they have returned 62,000 images and 86 gigabits of additional science data."
Spirit and Opportunity have also roved through the worst of the Martian winter with flying colors, and spring is on the horizon. Both rovers are in "strong positions" to continue exploring, Erickson said. "I can't tell you a timetable and in fact bad things could happen to us at any time," he cautioned. "Random part failures could lose emissions tomorrow. In addition to that, mild dust storms are kicking up now around the equatorial regions where the rovers are and that may impede the rovers' ability to collect solar power even though their arrays that have remained cleaner than anticipated. "But as long as we have them we're going to keep using them to the best of their ability," he assured.
Beyond being the darlings of the day, Spirit and Opportunity are the most heralded robots of 2004. In December, the journal Science honored the MER mission for producing the "Breakthrough of the Year," for the rovers' "profound implications for society and the advancement of science." ["On Mars, A Second Chance for Life," Science 2004 306: 2010-2012].
"It's very difficult even from the distance of a year to put the findings of this mission into their proper perspective," Squyres said, as he was officially handled the floor. "To me, the most remarkable story of today, is that the rovers are still going and they are still making remarkable scientific discoveries," he added, anxious to share some of the MER mission's most recent findings.
Spirit from Gusev Crater
"Spirit has moved into something totally new," Squyres continued without missing a beat. "We have suddenly, in the just the last few weeks, come into a completely different geologic material unlike anything seen on Mars before. This came as a complete surprise to us. I lost a bet on this one," he added, drawing laughter.
The MER team found its latest surprise in a rock called Wishstone, and another dubbed Wishing Well that Spirit is examining now. "We did some measurements down in the interior of [Wishstone] and what we found was a rock that was really different from anything we've ever seen on Mars before, even in the Columbia Hills, we have not seen rocks like this before," Squyres explained.
Wishstone is a rock composed of grains -- "one a geologist would call a iclastic rock," Squyres elaborated. "But the grains have enormous ranges of sizes -- it's a poorly sorted rock. Now, there are many geologic processes that make rocks out of grains that will make all the grains the same sizes . . . but this isn't like that. This [rock] has grains of all sizes from very small to very large and that tends to indicate that it was put into place in a very high-energy environment. It happened fast. We've seen this before in the rocks of the Columbia Hills, but this is another, a different indication of that. Some of these grains are very angular, look sort of busted up, which may also speak to a rapid violent process involved in forming this rock."
The two obvious candidates, Squyres continued, are some kind of geologic explosion or an impact process. "It's difficult to tell the two apart, but probably one of those two was responsible for making this rock." The "weird stuff" emerges in the chemistry. The first message is that [this rock] is dramatically different from anything we've seen before. The second things is . . . this rock is chock full of phosphorous . . . a much higher phosphorus content than anything we've seen on Mars before."
There are a couple possible explanations for the rich phosphorous content, Squyres said. "One possibility is that the igneous rock itself was rich in phosphorus to start with -- it was a primary mineral in the rock. The other possibility is that it was a phosphate that was deposited from water. That's a possibility we are pursuing. If it is what happened, then it speaks of a water chemistry dramatically different from what we saw just 500 hundred meters away on the West Spur . . . [where] we saw chlorine, sulfur, bromine -- elements that are way down in this rock.
"Somehow [Wishstone] is telling us something about a dramatic difference in the water chemistry, somehow the water chemistry changing with position or with time," Squyres explained. "There are some ways of making phosphates that involve water; others do not. As we look at a family of these rocks together, we should be able to test between those possibilities."
In coming sols, Spirit will continue to work her way up the crest of the Cumberland Ridge that leads to the summit of Husband Hill, stopping for research at a place on the crest dubbed Larry's Lookout. The rover has been experience no small amount of slippage during her climb, and so it has been slow going for the last week or so. But the team is confident she'll make it.
"The phosphorous-rich rocks we've seen so far are what geologists called float -- they're just sitting out on the surface -- they are of questionable pedigree," explained Squyres. "We want to find some that are rooted to the ground and we think by climbing up the Cumberland Ridge we'll find them."
Once she arrives at Larry's Lookout, Spirit should be able to see into the valley on the far side and see if there is any more bedrock there," Squyres noted. Her agenda from there will depend on what she sees.
Opportunity from Meridiani Planum
As Opportunity has roved south from Endurance Crater, up to and around the two pieces of her heat shield during the last week, the scientists have been having fun. "We get to sit back and let all the engineers do the really hard thinking and we just take pictures and make the engineers happy," explained Squyres. "It's a complete reversal of role -- and it's kind of cool."
Opportunity's current objective is to get up and image the debris with the panorama camera (PanCam), as well as the microscopic imager (MI) to determine how it handled the blast through the atmosphere. The rover is driving around the back side of the flank portion of debris to acquire images of the heat shield's perimeter. Once her work there is done, she will take a long drive to the south, heading for an area called Etched Terrain, which the science team homed in on for study months ago.
"It's going to be a connect the dots affair," said Squyres, as he indicated the number of small craters on an image of Opportunity's landing area taken by the Mars orbital camera (MOC) aboard the orbiting Mars Global Surveyor, and projected on the movie screen behind him. "We're going to hop-scotch from crater to crater -- and our first key objective is a circular feature we call Vostok. It's sort of crater-like in appearance but its funny looking . . . we think it's a strangely eroded impact crater.
No matter what happens from this point forward, Spirit and Opportunity can retire as champions at any point from here on out. They have given scientists enough data to keep them busy for decades. Their riding-off-into-the-Martian-sunset ending is already written. "They could die tomorrow, a month from now, or a year from now," summed up Manning. "Whatever happens, it has been a fantastic journey for these two rovers."
"For all of us, this mission with Spirit and Opportunity has been -- in the very literal sense of the phrase -- the adventure of a lifetime and I know I speak for the whole team when I say how fortunate we feel to have been able to be a part of it," a humbled Squyres said. "I think by any reckoning, the legacy, the lasting legacy of this mission is going to turn out to be the recognition that our sister planet, Mars, once had habitable conditions on its surface. What that meant for the origin of life and what it meant for the evolution of life, that's for future Mars programs to determine . . . but I think we have set the future Mars program a direction and a goal to pursue."
While NASA has had plenty of opportunity to review and analyze causes of failures in the recent past, Elachi, Squyres, Erickson, Manning and others on the MER team had no trouble identifying the root cause of the MER mission's success. In two words: teamwork and resources.
"The biggest thing that we have is the teamwork and the people involved at JPL -- both the people who did the design the operations, the original thoughts, the team that came with Dr. Squyres from across the country and across the world all working together -- that was what led to the success of this mission," offered Erickson.
"This was just an extraordinary group of individuals that did these rovers," Squyres concurred. "When we needed resources we got them -- from the agency, from the Jet Propulsion Laboratory, and we got the people we needed and these guys did things right. It's as simple as that."
Following the press conference and storytelling session, the camera lights were turned off, and Elachi gathered many of those who worked on the mission for a team picture as most of the jounralists headed out. Then everyone shared in cake -- strawberry and vanilla, and German chocolate -- a nod maybe to the German team from the University of Mainz which has contributed and are managing the Mössbauer spectrometer and the alpha particle x-ray spectrometer (APXS) on board the rovers. [The actual rover birthday cake had already been ferried to secure quarters for undisclosed purposes.] It was there, in those relaxed, mingling, lingering moments after the day's events, that the faces of the MER team seemed to mosaic together, becoming both the medium and the message of the magic that still awaits.