July 7th, 2003. A one hundred ton Delta II rocket streaks from Cape Canaveral into the night sky, carrying an advanced robotic explorer destined for Mars. The rover is named Opportunity, and together with its brother Spirit which launched the previous month, it will undertake the most extensive exploration of another world in human history.
Those watching the launch from the parks nearby might be forgiven for envying those skyward explorers. Planet Earth has had a rough ride, recently. The tragedy of the September 11 attacks has shattered the comfortable status quo of the post-Cold War world, leaving the War on Terror in its place. The invasion of Iraq is only 4 months old, and it's just becoming apparent that “mission accomplished” will require more than regime change. Anxieties are high and the battle lines that will define a decade of upheaval, at home and abroad, are being drawn. And hidden deep within the arcane world of global finance are the seeds of a crisis which will further define a generation.
Spirit and Opportunity are running about as far as its possible to go, but they've had to overcome obstacles of their own to even get this far. “That they were in Florida at all,” recalls Dr. Steve Squyres, principal investigator of the Mars Exploration Rover program and author of Exploring Mars, “was a small miracle.”
Just 4 years previously, in late 1999, two NASA spacecraft disappeared in the final stage of their journey to reach Mars. It was a humiliating blow for the Mars program, not least because of the reason for one of the losses: miscommunication between two teams using imperial and metric units. That elementary error, common in high school science classes around the country, caused an ignominious end to a 700 million dollar program, and left the Space program with something to prove. Mars missions, not easy to fund in the best of times, would face uphill battle to convince NASA and the American people that they were worth the risk.
Still, there was a lot of interest in exploring Mars, thanks to the discovery of what appeared to be fossilized bacteria on Martian meteorites. Mars had always been the nearest, most accessible candidate for planetary exploration, and it looked like it was also the best place to look for extraterrestrial life. The Mars Pathfinder mission, with its charismatic rover Sojourner, had been a great success, so in 2000 NASA approved another rover mission to Mars. The team who would build it now had three years to design and build a rover which could operate in frigid Martian weather, survive the trip through space, and a plunge through the atmosphere. To increase the odds of success, NASA asked them to build 2 rovers.
It was an ambitious plan. At the Jet Propulsion Laboratory in Pasadena, CA, the nation's top space engineers and scientists worked around the clock to solve the problems and invent the technologies that would make the vision a reality. For a nation flush with budget surpluses and still riding high as the world's only superpower, it seemed just this side of possible.
A modern spacecraft contains innumerable moving parts, computers, and instruments, and not all of them are made in the same place. Spirit and Opportunity had cameras manufactured at Arizona State University, a spectrometer from Johannes Gutenberg University, Germany, and a specialized drilling tool from a company called Honeybee robotics, located in New York city about a mile away from the World Trade Center towers.
On September 11th, 2001, 2 planes crashed into the World Trade Center buildings, killing almost 3000 people in what instantly became the defining moment of a generation. In the fallout from the tragedy, people all over the world felt helpless. At JPL, the idea of using Spirit and Opportunity as memorials for the events of that day was suggested, and quickly picked up steam. A month and a half later, an aluminum plate was delivered to the Honeybee building and quickly reforged into cable shielding for the rovers, which would protect their delicate wires from impacts. To this day those two components solemnly sport American flags, memorials to the victims of that horrible day standing at the far edges of human endeavor.
In the following years the technologies grew and the rovers gradually took shape. In the wider world, the US invaded Afghanistan, then Iraq. The Euro became the official currency of 12 EU nations, gradually growing to include several more. On February 3, 2003, the space shuttle Columbia broke up during reentry, killing all 7 members of the flight crew.
Still the crew of the Mars Exploration Rover team soldiered on, working to meet the launch window. It was a nonnegotiable deadline, resulting from a rare conjunction of the planets. Any delay would push the mission back to 2005, with serious ramifications for the likelihood of success.
So while the spectacle of Spirit's departure from our planet on July 3, 2003 was incredible for anyone watching, it was especially poignant for the team who slaved over the two rovers in the first place. It was out of their hands, now, embarked on a journey that would take it unthinkably further than even the Apollo astronauts had ever gone, so far that light itself would take up to half an hour to make a round trip.
It took 6 months to make that trip, 6 months of patient (and, one can imagine, at times not so patient) waiting until that most nerve-wracking of moments, planetfall. Planetfall occurs when the spacecraft transitions from spaceflight to becoming a lander, impacting the atmosphere in as controlled a manner as possible so that it slows down enough to reach the surface without splattering into it. As if to emphasize the danger inherent in this complex maneuver, the European Space Agency's Beagle 2 lander suffered a catastrophe during landing on December 25, 2003, just 11 days before Spirit was scheduled to land. It was never heard from again, and presumed to have impacted the planet at too high a velocity.
Finally, the day came. Press from around the world surrounded the command center at JPL, waiting for images from the red planet or news of another disastrous failure. It is probably fair to say that the future of the Mars program in general, at least for the near future, rested on the successful landing of the rovers and completion of their 90 day mission. Failure would mean no more political will to extend humanity's reach on our nearest neighbor, especially in light of the Columbia tragedy. Success could mean proof of water on Mars and scientific strides that might pave the way for a manned mission.
On January 4th, 2004, Mars Exploration Rover A, Spirit, touched down successfully at Columbia Memorial Station, a landing site named in honor of the fallen space shuttle. Spirit then broadcast the highest resolution image ever taken of another planet, a panoramic color view of the landing site. It was all that was needed to declare the landing a success. Now came the hard work of 90 grueling days of mission operation, with the scientists and engineers of the project living on the same 24.5 hour day that the rovers were experiencing. Spirit might have been alone on the surface of an alien world, but JPL staff were joining it every Martian morning by virtual commute from California to Mars.
The next few days proved to be tricky. Identifying potential sites of interest for the rover to examine had just begun when contact with the rover was lost. A few blips of data were received now and then, but what was originally thought to be a weather disturbance quickly became a threat with the potential to end the mission before any of its scientific objectives were realized. Worse, Opportunity was fast approaching the planet, and the engineers who needed to focus on its equally risky landing were distracted by the problems with Spirit.
On January 25th, Opportunity experienced a picture-perfect landing, arriving in the middle of an unexpected crater of geological interest. It was named Eagle Crater, and the rover scientists called the landing an interplanetary “hole in one”. With the world caught up in concern about avian flu emerging in South Asia, Spirit was also back up and running by early February. It was a good month for the space program.
On March 11, 2004, Spirit transmitted the first image of Earth taken from another planet. The symbolism of that gesture, looking back at the fragile vessel which holds our collective histories, was undermined by the simultaneous bombings of numerous commuter trains in Madrid, killing 191 people and injuring almost 2,000 more, that very same day.
In April of 2004, with the US just getting down to the business of the oncoming Kerry versus Bush election, both rovers surpassed the guideline NASA had set out for a successful mission by operating for 90 days on the Martian surface. Because the rovers are solar powered, it had been anticipated that dust buildup would prevent the rovers from operating long past that point. NASA planners judged that 90 days of operation would justify the expense and risk of the mission.
Spirit lasted for 2210 Martian days (more than 5 years), and Opportunity remains operational as of the end of 2011, trekking across the Martian surface in pursuit of new regions to explore. During that time they greatly expanded our knowledge of the Martian surface, including close up views of conclusive evidence that water once existed on the Martian surface. Those years were filled with many other milestones, both for the intrepid rovers on Mars and for those of us still on Earth.
In January 2005, Opportunity identified the first ever meteorite found on another planet. Both it and other space probes had investigated craters before, but this was the first time that an actual meteorite was scene and examined on a world other than earth.
On March 10, 2005, Spirit photographed a dust devil moving across Mars in a rare and lucky break. A similar event was probably responsible for clearing much of the dust that had been accumulating on its solar panels, probably increasing the lifetime of the mission significantly. Here on Earth, CBS Evening News anchor Dan Rather signed off for good that same night.
During 2007, Opportunity explored a feature known as Victoria crater, which provided natural cross-sections of Mars rock strata. During this time, both it and Spirit weathered massive planet-wide dust storms which threatened to cut off their power supply completely. The scale of these dust storms are unprecedented here on Earth, as they affected both of the rovers for the entire month of July, despite the fact that they were on opposite sides of the planet. It was a stormy month here on Earth, as well, as fatal bombings rocked London's mass transportation, a mall in Israel, and a resort town in Egypt.
Nothing lasts forever, and despite the machines' incredible hardiness the years took their tole. On May 1, 2009, after five years of operation, the rover Spirit became stuck in abnormally soft sand hidden just below the soil surface. Over the course of the next year, engineers attempted to extricate the rover until it was declared a mobile research platform on January 26, 2010. A few months later, on March 22, the last communication from Spirit was received. Attempts to reestablish communication would continue until, 3 days after the supposed date of of the Christian rapture (famously predicted by Harold Camping), Spirit was officially given a farewell on May 25th, 2011.
Opportunity is still chugging along, and participated in more milestones over the next year. In August it arrived at Endeavour crater, the culmination of a 3 year, 13 mile trek across the Martian landscape. In September it photographed the section of its assembly forged from debris from the World Trade Center towers, in commemoration of the tenth anniversary of that tragedy. Then in December, it broadcast an analysis of a vein of rock it identified as gypsum, in what has been called “slamdunk” proof that liquid water once flowed on or through Mars. Its mission of exploration continues into the new year, and beyond.
On November 26th, 2011, the Curiosity rover was launched from Cape Canaveral and flung out towards Mars. Its mission is similar to the rovers that preceded it, though it is larger, more capable, and packed with more instruments than they were . It's mission is also more explicitly aimed at gathering data to help in ongoing planning for an eventual manned mission. Without the success of the Mars Exploration Rovers that preceded it, it would never have gotten off the ground.
With everything demanding our attention here on Earth, it is understandable that many people want to devote the resources we have to addressing problems close to home. In an earlier world, with our country flush with prosperity and facing down the Soviet Union, an extravagant space program was perhaps a luxury we could afford. But we no longer live in that world.
It's sometimes hard not to feel that ours is a nation, even a world in decline. The steady drumbeat of conflict, global warming, economic problems, and doomsaying takes its toll. The zeitgeist is full of anxiety that our ambitions for the future must be less than the triumphs of our history.
Spirit and Opportunity were born in that world, even if they were destined for another. The people who gave them life knew that their mission was do or die, either redemption for a program haunted by high profile failures, or proof that it was too risky and expensive to justify. They poured their lives into succeeding where many had failed before, on a scale that was unprecedented, with a time limit that seemed frankly impossible. Then they did it twice.
That they succeeded at all isn't just impressive, it is inspiring. That they succeeded so far beyond even their most optimistic dreams is incredible. The story of Spirit and Opportunity is a true epic, an untold story of triumph in a decade of upheaval and tragedy.
The world spins. Governments rise and fall, fortunes are swindled, and network news blares about a new study detailing the dangers of red meat. Two hundred million miles away, the most hard working astronaut in history patiently sifts through rock samples under an alien sky, waiting for a time when its human comrades can join it among the stars.
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