Review: Roving Mars
by Phil Smith
|Roving Mars conveys the deep satisfaction that Squyres feels as he reflects upon the roller-coaster ride that began as a dream and, well, hasn’t actually ended yet.|
In 1987, after five years working for NASA and teaching for a time at Cornell, Squyres finally finds an opportunity to pursue a role in an upcoming Mars mission. He finds it after having a conversation with an engineer at a symposium in Moscow, a chance meeting that leads to the development of several camera concepts over the next decade or so. Squyres recounts in detail the nervousness felt when sizing up the competition, the strain of making sure all the parameters listed in NASA’s request for proposals (RFP) are met, and the stress of just waiting to find out if you won. Needless to say, we feel only a fraction of the letdown felt by Squyres as he and his team lose one after another proposal until, finally, after a long, convoluted series of events unfold, a unique opportunity presents itself.
The seeds that eventually give rise to Spirit and Opportunity find their genesis in 1992, when NASA released an RFP for the Mars Environmental Survey, or MESUR, mission. MESUR was to consist of sixteen identical Mars landers. A prototype mission called MESUR Pathfinder was to be launched first before the flotilla headed for Earth’s neighbor. By that time, Squyres and his original team had actually built a fully-functional panoramic camera for a previous proposal effort. This camera served as inspiration for another designed by Squyres and a new team for MESUR Pathfinder. Unfortunately, Squyres’ team misread NASA’s original RFP, and the team’s camera was rejected.
Shortly after Mars Observer was lost on its way to Mars, MESUR was cancelled, though Pathfinder remained in the queue, without Squyres’ camera. A new Mars mission slated for 1998 was requested by NASA in 1995, though this time teams were asked to develop an integrated suite of instruments. In response, Squyres led a team to develop a mobile geological tour-de-force. Once again, Squyres’ team wasn’t picked, and NASA went with the Mars Polar Lander, a mission ideal for core sampling of ice, and not for a rover. At this point in his book, we develop a kind of exasperation that only hints at the devastation Squyres felt, eight years after submitting his first proposal for a Mars-bound instrument and 18 years after making the decision to explore Mars a professional objective. Had we not known of the success of the rover missions to come, one would wonder if Squyres would ever get to Mars.
While NASA was futzing around with its ever-changing Mars program, Squyres came up with a plan that would avoid the pitfalls common with shifting Mars plans: NASA’s Discovery Program. Discovery had its own budget, independent of the Mars program, and would allow Squyres and his team to do it all—to build the whole machine instead of an instrument or suite of instruments. In 1996, Squyres and his team founded Athena, a sort of Pathfinder on steroids. Athena was taking shape just as a researcher at NASA’s Johnson Space Center announced he may have found fossils in a Martian meteorite. To Squyres, this was good news, since the only way to confirm such a possibility was to send an agile rover to Mars, and their Athena was certainly that. Interestingly, NASA’s Mars budget was substantially increased during this time, and the Athena project didn’t make it as a Discovery mission. After significant recasting work, Squyres got Athena into the queue as a 2001 Mars mission. Needless to say, life got even more complicated as two Mars missions ended in failure in 1998, and NASA was forced to reconfigure its approach to Mars. By 2001, Athena was transformed into what we recognize today as the MER, and because NASA Administrator Dan Goldin wanted assured success on the next Mars mission launched in 2003, he ordered two exact missions. For Squyres, after so many years of ups and downs, this was truly a dream come true.
|For Squyres, watching the rovers head into space was both a relief and the beginning of a new adventure the whole world would share with him.|
Squyres’ book then describes the development of Spirit and Opportunity, particularly focusing on the relationships between the scientists and engineers working on the project from all over the world. Each instrument, like the now-famous Mini-TES, Pancam, and Mössbauer spectrometer, had its own development team. Squyres, as the principal investigator for MER, oversaw everything related to the science mission. He was also part of the incredibly nerve-wracking payload-launch vehicle integration, in-flight monitoring, and navigation and descent. We see through his eyes the horror of mysterious glitches that required investigative measures that would make the FBI proud, and the potential nightmare unfolding as parachute tests failed one after another just days before delivery. Squyres does convey his admiration for the rovers as they take shape, and by the summer of 2003 one immediately appreciates his bittersweet feelings as each depart Earth never to be seen again. Would they make it? Did we do everything right? For Squyres, watching the rovers head into space was both a relief and the beginning of a new adventure the whole world would share with him.
Spirit and Opportunity arrived on Mars less than a year later, both bouncing around on the surface within their balloon capsules. Every single complicated maneuver took place without a hitch, and Squyres does convey the sense that everyone affiliated with the MER program was pleasantly surprised by the flawless mission profiles. Clearly this was a testament to the team’s talent, something Squyres mentions throughout the book (at the end of the book, he even includes a lengthy list of all those people who worked on the program).
On the surface, Squyres found himself less impressed with Spirit’s landing site, Gusev Crater, than that of Opportunity’s landing site in Meridiani Planum. Gusev was supposed to reveal evidence of water almost immediately, since orbital images of the crater clearly showed that it was filled with some sort of fluid billions of years ago. Instead, the crater was littered with basaltic boulders reminiscent of the Viking landing sites. This was not totally unexpected, since Gusev’s sedimentary evidence could have since been covered up with lava flows. A deep crater could reveal the sediment below, but such a crater near the landing site, called Bonneville, was a disappointment—it literally looked like a giant, featureless bowl. Spirit headed for the hills some three kilometers south of the landing site, and finally the little rover found evidence of water by discovering various salts, though sedimentary rocks have yet to be found. As this review was published, Spirit is on top of Husband Hill looking around at the landscape below, soaking in the big picture. Its next destination has yet to be publicly announced.
Opportunity, meanwhile, having literally landed in a small crater in the middle of a vast wasteland of hematite (the team called the little crater Eagle), found itself staring right at a matrix of sedimentary rocks shortly after landing. In the book, Squyres admits he had no idea what he was looking at, but the reader, having got to know Squyres a bit by this point, knows the scientist is relishing this kind of unknown. The surface around Opportunity was certainly alien, as it became apparent the entire area was covered with countless little blue beads, found later to be hematite. These hematite beads, and the rock bed almost circling the crater rim, would ultimately provide the necessary evidence that standing water, though not much of it, was present on Mars long, long ago. As far as the MER primary mission objective was concerned, finding evidence of water on Mars, the taxpayers got exactly what they paid for, and a new era in Martian science was born.
|The book provides the reader with an appreciation for the difficulties involved in developing an extraordinarily complex mission whose true nature is betrayed by the flawless results of a very talented team.|
The rover ended up staying in Eagle for months before emerging and heading to the next, much larger crater called Endurance. This crater was definitely not like Bonneville, and it became clear Opportunity would be staying there awhile. More ancient evidence of water was found in Endurance in the form of salt-laden layered rock. Opportunity eventually left Endurance for a region of “mottled terrain” south of the area, finding remnants of its heat shield along the way and, interestingly, an iron meteorite sitting in the open. On its way south, Opportunity got stuck in a deep dune, extracting itself weeks later and resuming its journey across the dune field. Recently, Opportunity has found much more bedrock as the dunes have thinned out.
Roving Mars is a fascinating account of how a scientist with a dream to explore Mars finds his way to making the dream happen through collaboration with other scientists and a team of engineers. It provides the reader with an appreciation for the difficulties involved in developing an extraordinarily complex mission whose true nature is betrayed by the flawless results of a very talented team. While my main interest focused on the science these rovers were gathering, I found the sometimes technical description of the engineering, political, and budgetary hurdles inherent in any NASA mission to be truly interesting. Squyres’ “regular guy” approach to writing the book makes one feel like part of his team, waiting by the phone hoping to hear that NASA has chosen your plan for the next mission to the Red Planet.
I highly recommend this book not only to those interested in the complicated interactions between scientists, engineers, and managers, but also to those who want to know how this relatively small group of people managed to use a modest amount of our tax money and squeeze every bit of value out of it. Indeed, both missions continue to reap benefits for us almost two years after they landed.