A Better, Vanished Time

When I was 15, half a lifetime ago at the present moment, my uncle Ted took me on a flight in a World War 2-vintage observation aircraft that was kept in flying condition by the museum where he and my grandfather, his father, volunteered. He decided to execute a tight turn onto final approach and it felt like he flipped the airplane on its side as we lined up. The senses humans evolved with are not well suited to understanding the dynamics of flight, and we probably didn’t bank any more than 45 degrees, but it felt like we were about to go over with only a few hundred feet of altitude beneath us. “Whoa!” I shouted, and pushed the stick back toward center, evening out the bank to something more comfortable.

Looking back, this was a singularly bizarre moment in my life. Like my grandfather, Ted flew for the Air Force (Army Air Force in Grandpa’s time) during a time of war. Unlike my grandfather he repeatedly flew into combat in unarmed aircraft. During his service in the Vietnam War Ted earned an Air Medal and a Distinguished Flying Cross for his technical skill and devotion to duty. He also became proficient in the supersonic jet trainers that killed the astronauts Ted Freeman, Elliot See, Charlie Basset, and CC Williams in training accidents. Now here I was, a punk teenager with about 10 hours of dual instruction in gliders, correcting his flying with tactile force. In retrospect, I’m embarrassed. On the other hand, he didn’t dress me down for it after the flight. Perhaps Ted understood more than most pilots that experience and skill don’t prevent you from occasionally forgetting that an Aeronca can’t be made to handle like a T-38.

On Saturday I made the drive from my family’s new home in Seattle to Ted’s house in Richland, Oregon, a speck of a town in about as remote of a location as you can find in the contiguous 48 states. The drive took me through Snoqualmie Pass, through the deserts and farmlands of eastern Washington, across the wide blue churn of the Columbia River, and along the home stretch of the Oregon Trail so worn down in the middle of the 19^th Century. It’s as perfect of a 400 mile drive as I’ve ever been on, and I’d recommend it as the best possible introduction to the Pacific Northwest. Ted’s immune system and his doctors had been fighting cancer for the last several years and I knew that this was likely to be the last time I would see him.

We spoke to each other a few times that afternoon. I told Ted about my children and about the work I’ve recently begun at Blue Origin. I told my son that I was visiting my uncle, who was sick, to try to cheer him up, and he asked me to show Ted a heart that he made in preschool to help him feel better. I showed that to Ted and he seemed amused. It was good to hear his voice, though it was clearly hard for him to say much and I did most of the talking. I sat and looked at the southern reach of the Wallowa Mountains, listening to the rustle of wind through the leaves, watching the swallows and magpies dive and dart for insects, trying to contemplate life and mostly just settling for breathing. Early the following morning Ted died at the age of 74.

Maybe that doesn’t seem like much of a climax to a life intensely lived, but life doesn’t follow the neat narrative structure of our stories. The true narrative of living is more of a drunkard’s walk from event to event, sometimes in misery, sometimes in joy, hopefully in love. Roger Ebert had it about right in his review of O Brother, Where Art Thou! It’s like The Odyssey, in the sense that it’s one thing after another.

Between the bookends of his life Ted found plenty of drama and tragedy and comedy to fill that narrative space. Besides rooming with a future Space Shuttle astronaut at the Air Force Academy and serving in Vietnam he raised three children and went through the infernal microcosm of medical school and residency that my wife has just surfaced from. He found love and companionship late in life much like the ideal love of youth. So many lives were cut short by that insanity in southeast Asia, but he was one of the ones who got to come home, and he made the life he lived here, in California and in Oregon, worth living. You’re catching me at the wrong time to say anything positive about the medical establishment, but surely his service here, helping so many lives over the decades in little and big ways, merits some kind of meaning to the chaos of life in general and his life in particular.

I won’t pretend that I was one of the most important people in Ted’s life. In Richland this weekend I saw his children and grandchildren, his wife, and his brothers (my father among them). But when I saw him he was always welcoming and joyful and loving. He put up with my crap when I complained about finding parking in downtown Seattle. We rode four-wheelers (reminding me a bit of the setup to Rush's "Red Barchetta") and shot at targets and drank beer and watched a total solar eclipse in Richland. Before that I have so many wonderful memories of seeing him during my visits to California and his visits to Arizona. I consoled him when his father died, and he consoled me when my brother died. So much and yet, at the end, never enough.

Jeremy Frampton was one of the 12 killed during the collapse of the Aggie bonfire pile in 1999. Part of his memorial is this poem he left behind:

If I stare long enough

If I talk hard enough

If I touch soft enough

If I love deep enough

Will I live long enough

To love life enough

I am haunted by the question, which is sort of another way of saying that I don’t understand the human condition. I suppose no one really does and my desire to want to own this and understand it completely is an occasion of the sin of pride. Still, unlike the trees and the magpies and the locusts and the fungi, we can see the roadmap from birth to maturity to reproduction (if we’re lucky) to death, and we want to make sense of something that nature has given us nothing to make sense of.

The point isn’t that a life well lived and death well planned, in a home surrounded by beauty and love and family, makes death easy. It’s still awful, though less awful than anything else. I’m glad at least that Ted took what was out of his control with grace and masterfully crafted what was in his control to the life he wanted, to his last day. I’m so glad that I got to have him in my life for my first three decades.

Hull Loss

Huntsville, Texas. With apologies to the community, there is little to distinguish Huntsville geographically from the litany of towns its size across Texas. From the Gulf of Mexico to the Red River there’s a wide swath where the prairie meets the forest in gently sloping hills, where the highways and farm to market roads cut across wildflower patches and cattle pastures between the thickets and the downtown thoroughfares. Huntsville just happens to be one of them, and when it appears in the news it’s usually because it happens to also be the primary center for executions in the state of Texas, where the lust for legal human blood runs hottest in the nation. Should the United States ever establish formal diplomatic ties with Thanatos, it would be a natural location for a consulate. I was more interested in seeing the 67-foot-tall statue of Sam Houston that also happens to be located there, so once on my way back to College Station from north Texas I took a detour through the town. This is the furthest east I took the first car I ever owned, a 2007 Honda Civic.

Big Bend. A poet once lamented that Mexico is so far from God and so close to the United States. The latter part feels viscerally true in Santa Elena Canyon, tucked away in what might be the most remote of the national parks in the contiguous 48 states. The Rio Grande River cuts through limestone laid down during the Cretaceous Period here, leaving two imposing cliffs vaulting toward the sky above the hiking trail that follows the curve of the river. It seems at places you could extend two hands, the fingers of one grazing Texas and the other touching Chihuahua. I was struck by the silence of the place. It was so quiet the silence felt immersive, like a tsunami of stillness washing over me. After dark I drove the Civic to an empty patch of desert and lay down on the trunk and rear window to watch the stars. The Moon seemed so bright this far from civilization that I wondered how it could possibly be just a reflection of the Sun. This was the farthest south I took the Civic.

Boston Bar, British Columbia. I grew up not far from the canyonlands carved by the Colorado River and its tributaries in the American southwest, so the gross topography of the Pacific northwest wasn’t wholly unfamiliar to me when I first arrived there. The life there was really something else, though. The shades of green of conifer trees, their deciduous cousins, ferns, and mosses seem to cover every square inch not cultivated and tilled by humans or water. The effect is magnified further at some distance from the great city centers of Seattle, Portland, and Vancouver. I was reminded, driving through the Fraser Canyon, of Gordon Lightfoot’s ode to the wilderness spanned by the trans-Canada railroad, how long before the white man and long before the rail the land was “too silent to be real.” It was easy to fall for the illusion here that the planet Earth is wide enough for humanity to grow forever and always enjoy a wild homeland. Eventually I felt I’d wandered far enough from home and turned around at some undocumented furthest north.

Cape Flattery. Heading northwest from the centroid of the contiguous United States, this is the end of the line. Cape Flattery is the extreme tip of the Olympic Peninsula. Depending on your frame of reference, this is either where the North American continent yields all at once in a series of cliffs to the wild Pacific Ocean, or where the ocean acknowledges the land, transitioning from thousands of miles of open water to the sheltered Strait of Juan de Fuca. There was nowhere further west for the Civic to drive. When I arrived there I didn’t feel moved to peruse the safety signage and since the bounds of the trail were poorly marked I found myself dangling my feet off the edge of America. It was a wonderful moment, sharing wordless communion with the bald eagles soaring on the ridge lift of the bluff and watching the sunset colors begin to show in the cloud formations off Vancouver Island. It began to snow on the ferry ride across Puget Sound on the way home, and the slippery drive up the Edmonds hill turned out to be the only time I ever drove the Civic in significant snowfall.

Those are the extreme points where I drove the Civic, but of course there are countless other trips and excursions contained within those corners. It was a real workhorse of a car. Several times it made cross country trips. Phoenix to College Station. College Station to Boulder. College Station to Phoenix. Phoenix to Seattle. Seattle to Glacier National Park. Seattle to Los Angeles. It was a machine at home chewing up the miles. There’s a stretch of I-10 in west Texas as remote as the Australian outback, where the speed limit is 80 miles an hour. The Civic comfortably cruised at 90, and I’m sure I could’ve pushed it further, but that sort of excess seemed unnecessary.

Most of the trips the car made were mundane and forgettable. I wonder now what percentage of the vehicle’s odometry was devoted to trips between Green Lake and Tukwila, Los Feliz and Long Beach, Los Feliz and El Segundo. These commutes were all unique, the way each moment of life is unique, but in memory virtually indistinguishable from each other. My brain seems unable or unwilling to give them any special significance.

By contrast, the trips I remember were remarkable. I was stunned the first time I drove through Snoqualmie Pass, approaching Seattle from the east by land. I drove through a world of mist and mountain, forest and lake that seemed like something straight out of a Hollywood interpretation of a fairy tale. I discovered a nameless patch of I-84 between Pendleton and La Grande that seemed so spectacular it might be a national park in a state less blessed with wonders of nature. Twice in quick succession the Civic took me to observe syzygies that will never occur again in my life. First, an annular eclipse of the Sun at the south rim of the Grand Canyon. Later that summer, across the Cascades and out of the rain to observe a transit of Venus in the clear air of Ellensburg. Many times I followed the hand signals of auto deck crews to park it uncomfortably close to the other cars being ferried around Puget Sound and the Salish Sea. I drove off to marvel at the little pocket worlds of life and color and land within the water in that corner of America.

The car had over 90,000 miles on the odometer when I bought it. That was a source of some concern. Several times it acted up or gave up on the road completely, and I had to sink a thousand dollars or more to keep it going, like a game over moment at the world’s most expensive video arcade. Still, the final score was nearly 232,000 miles, just one Earth diameter short of the average distance between Earth and the Moon. I wish I’d treated the car better during this time. As my life evolved and became more complex and stressful I lost the will to care for it like a loved possession. Still, it did its job for my family and me admirably.

I don’t remember what the last drive I made before my wedding was. It was probably from Boeing Field to Green Lake, after a relatively normal day of work, but it may have been some errand. It snowed the next day and I worked from home, then I called in sick and took a Lyft the day after to SeaTac. I departed that December a virgin and a bachelor and returned a husband and a father-to-be. Nine months later I placed a carseat in the back of the little red Civic and drove my newborn son home. I’m ashamed to say that I don’t remember for sure anymore, but I think this car also drove my daughter home from the hospital. Stress and exhaustion do remarkable things to a person’s memory.

On the morning of Good Friday this year I took my children to Dockwiler Beach. There was a marine layer overcast, so we couldn’t see much, but we heard the roar and buzz of jets taking off from LAX while my son and daughter dug sand and chased seagulls. I refueled in El Segundo and headed west on I-105, then north on I-110, as I did many times while I worked at ABL. That turned out to be the last road I ever drove the Civic on. Two cars collided at low speed, low enough that there were no injuries, that the gas generators in the airbags remained unignited, ready to protect in the event of more serious danger. The kids were unperturbed. The insurance declared repairs uneconomical and so I wrote off my ownership of this car that carried me so far, down so many roads, for the last nine years.

As I gathered my belongings from the car I took a moment to pause in the driver’s seat and think of the time I’d spent there over the almost-decade I’d owned the Civic. It served my family well, and for that I’m grateful to the team at Honda that designed it and the team in East Liberty, Ohio, that assembled it. On Wednesday this week my wife and I signed the paperwork to begin ownership of the first new car we’ve leased together as a family, a Ford Fusion Hybrid designed in Michigan and assembled in Hermosillo, one of the sister cities of my hometown. Driver interface technology has advanced so ferociously in the last decade that it feels like a completely different sort of vehicle than the Civic. If the Civic was a go-kart, the Fusion is a starship. I hope and believe it will serve our family well, just as its predecessor did.

To Dust You Shall Return

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The Book of Genesis is one of the oldest pieces of writing that has survived to modern civilization. One of the reasons it’s stayed in our collective memory so long is that it communicates profound truths about the universe, life, and humanity. In describing the creation of the universe, Genesis doesn’t assign an initial condition of void or nothingness. Before light, before the great mystery that willed the universe into being, the abyss is described as water. Such, the scribes who put ink to parchment all those millennia ago imagined, it was at the beginning.

Perhaps this idea of water at the bedrock and basis of existence is not a truth of the universe, but it is a fundamental truth of life as we know it. Water is a not-quite-universal solvent, a carrier of ions, magically, wonderfully liquid across a wide range of temperatures and pressures. As creatures born of a watery ocean, we come with a biased perception, but it’s difficult to imagine a better medium to bridge the gap from chemistry to biology. Earth is lousy with water and equally lousy with life. As we learned that the universe is so much vaster than our home planet, it made sense to take an interest in water in the interest of finding how often the universe stirs from the slumber of Genesis.

In the present day only two worlds are known to be blessed with liquid waves washing their shores. Beyond the good Earth only Titan has lakes, seas, waves, and rain. But Titan’s oceans are a truly alien landscape. Water freezes to the consistency of steel at the surface, and methane flows through the rivers and valleys of Saturn’s flagship moon. Perhaps life teems in pockets of water deep under the surfaces of Europa, Enceladus, Pluto, and other icy worlds far afield in the outer solar system. I hope that one beautiful day this century a craft built by humans will report back the answer to these questions. For now, though, those isolated havens are out of the grasp of our technology and dreams.

The surface of Mars is a very difficult to place to reach by any reasonable standard. It can, however, be reached. Today the planet seems largely inhospitable to Earth’s simplest creatures with the greatest gluttony for living in extreme conditions. There may be pockets deep underground or in lakes beneath the polar glaciers that resemble Earth more closely, but the more interesting comparison between Earth and Mars comes with a look backward in time.

When I began high school the nature of Mars in the early history of the solar system was a controversial topic. The spacecraft that had orbited Mars found features that suggested the action of flowing water in the distant past. It was plausible to imagine that long ago Mars had oceans, or at least seas, mixing the same organic soup under the same sunlight as Earth. Perhaps, the thought went, those seas begat life like the seas of Earth. Then again, the three successful landers up to that time, the twin Vikings and Mars Pathfinder, had little to say on the condition of ancient Mars. There were plausible theories that didn’t require water and a thick atmosphere. Perhaps it was all a case of looking at a mirage and seeing an oasis in the desert of deep space.

In the summer of 2003 two spacecraft launched from Earth to settle the question. Their official name was an acronym in classic NASA fashion. MER – the Mars Exploration Rovers. Shortly before launching they were named Spirit and Opportunity.

From the start the mission had problems. Finding the ground truth of the state of Mars four billion years ago required being able to move a complex suite of spectrometers, cameras, and tools long distances. It was unlikely that a single rock in the reach of a robotic arm wherever a spacecraft happened to land would be able to give the full story. So the landers became little more than packaging to bring the big rovers down to the surface.

The MER program didn’t have the budget to run a science project to determine how best to get golf-cart-size rovers down to the surface of Mars. 30 years earlier the Viking program launched rockets to Earth's upper atmosphere to test parachute deployment in the most Mars-like conditions available on Earth. Spirit and Opportunity would have to make do with knowledge already gained. The engineers had the example of Pathfinder, and they extrapolated on it to its insane conclusion. The rovers were too big. The parachutes shredded when they inflated in tests over Idaho. The airbags burst over simulated Mars rocks. Meanwhile the planets moved in their orbits and the launch window approached.

The parachute team iterated as fast as they could and found a solution as the wife of the chief entry, descent, and landing engineer, Adam Steltzner, went into labor with their child. They added an additional stabilizing rocket motor to the entry capsule to halt sideways movement as the rovers approached the surface. Hopefully that would spare the airbags. They made their schedules and launched when the heavens ordained they must, but only just.

The night of July 7, 2003 was a typical summer night in Florida. At Jetty Park, just south of Port Canaveral, the air was hot and muggy and filled with the sound of insects and the watery surf of Earth crashing on the beach. Several miles to the north, at the appointed time propellant valves opened in the RS-27A engine powering the first stage of a Delta II launch vehicle. The gas generator ignited, pouring exhaust gas black as coal and hot as a blowtorch into the turbine. In a second the turbine spooled up, cranking torque through the gearbox and spinning the pumps to full power. A flame a hundred times brighter than the gas generator began burning in the combustion chamber, the nozzle turning its luminous energy into thrust slamming the rocket against its hold-down bolts, away from the Earth where it was made. Another second went by, and six of the nine solid rocket motors ignited as the hold-down bolts pyrotechnically split open. Opportunity, the second rover, the backup MER, was off, never to touch the Earth again. At Jetty Park bagpipes played "Amazing Grace" and after half a minute the overwhelming roar of sound from the motors and engine rattled in the ears and throats and bellies of all gathered there watching.

The ground-started motors burned out and fell away. The remaining three solids ignited, turned their propellant into steam, ash, acid, and kinetic energy, and fell away as well. When the RS-27A had consumed its fill of kerosene and oxygen the computer closed the valves to shut down the engine. The second stage ignited, and when the stack had climbed above the last reaches of Earth’s atmosphere the protective fairing fell away from Opportunity. Nine motors and two engines were insufficient for Opportunity to exit Earth’s gravity completely, so an additional spin-stabilized solid rocket motor ignited for the final push away. Within half an hour of that moment on the beach, the little rover would never again feel the water of Earth. It would one day, perhaps, feel the trace of water of Mars.

As it happened, the Earth-Mars transfer window of 2003 was very favorable. The two planets approached as close as they ever have in the modern history of astronomy during that autumn, and six months later Spirit made her successful landing at Gusev Crater. On January 25, 2004, it was Opportunity’s turn at the gauntlet of atmospheric entry.

Mars is a much smaller planet than Earth. The transition between interplanetary cruise and deceleration in the atmosphere is governed by the mass of the planet. Smaller planet yields smaller orbital speeds and thus lower atmospheric entry speed. Opportunity hit the top of Mars’s atmosphere at a lower speed than a spacecraft returning to Earth from low Earth orbit. From that relatively straightforward beginning, descent to Mars only becomes harder.

At its lowest points the density and pressure of Mars’s atmosphere is equivalent to the conditions high in Earth’s stratosphere. The speed of sound in a gas is a function of molecular weight and temperature. Mars is much colder on average than Earth, thus lower speed of sound. The upshot of this atmospheric balance is that the Martian atmosphere is unable to slow an entering spacecraft below the speed of sound unassisted. Like her twin Spirit and all other spacecraft that have successfully landed on Mars, Opporutnity had to deploy a soft parachute into air screaming by at twice the speed of sound. The work of Steltzner and his colleagues was weighed in the balance and not found wanting. The parachute stayed in one piece in the supersonic cacophony of deceleration.

Shortly before landing a solid-propellant gas generator fired and the airbags surrounding Opportunity’s landing platform inflated. The last set of solid rockets burned, bringing the rover to a standstill for the first time in six months a few meters above the dusty surface of Mars. A pyrotechnic initiator fired, cutting the cord between Opportunity and the last machine that would ever carry it. The rover bounced for a time in the leisurely gravity of Mars, then rolled to a halt in a little crater the team at JPL named Eagle.

Getting to Mars alone was hard enough. Landers since the MER program have improved their accuracy substantially, but it’s still not possible to say when a given spacecraft is launched where within a circle of a few miles exactly it will make contact with the Martian soil. Picking and landing in a crater the size of a baseball diamond from then next planet over is out of the question. It would require an absurd stroke of luck. Which is exactly what the MER team found when Opportunity raised her mast and showed that she had made landfall in a little crater with an outcrop a stone’s throw away. Within that outcrop the bedrock of ancient Mars was on display, ripe for the discovering.

Opportunity proceeded cautiously but impatiently. The rover was only certified to last for 90 Martian days. It was essential not to do anything that could compromise the workings of her delicate instruments, but it was also essential that she not fall asleep under the cold pink Martian sky before the cameras and spectrometers probed what they were there to find. So in those first few months Opportunity stepped off the landing platform and became a creature of Mars.

The dust of Eagle Crater was littered with ball bearing-shaped concretions. It was evident that the bedrock was full of them, and they were rolling out as the outcrop eroded away. As the instruments attacked the rock one by one at site after site the picture they revealed was unmistakable. For a long time, long ago, there was water here. Mars was warm. Mars had seas, perhaps oceans. Winds blew on sandy shores then, just as they do now on Earth. This was not circumstantial evidence, but ground truth.

The rover was healthy, so she pressed on. The plains of her new home, Meridiani Planum, were studded with meteorites. As the rover’s longevity became more apparent she moved from one crater to another. Endurance, Victoria, Endeavour Craters all hosted the rover for a time. The months became years. The staff on Earth went back to measuring their days in Earth time. The planets moved in their orbits. In Pasadena the seasons progressed through their cycle and in Florida the launches continued on their regular cadence. Phoenix joined the pair for an arctic summer. Spirit became mired in a sand dune and fell silent a year later. Curiosity arrived as Opportunity reached Endeavour Crater. Opportunity slowed when the dust accumulated on her solar panels, then leaped into action again when dust devils brushed them clean.

At Endeavour she found a vein of gypsum. Even more than the discoveries at Eagle Crater, this indicated a long, benign period in the ancient history of Mars. There might have been little to distinguish Earth’s and Mars’s conditions at that time on the surface. We now know that bacteria and archea can survive the acceleration and jerk of asteroid impacts and exposure to space for years, perhaps centuries, at a time. The geological record of Earth and the Moon suggests that the time when life existed on Earth overlaps the time when Earth’s surface was routinely sterilized by cataclysmic impacts. All life on Earth began as space travelers, it appears. So, perhaps it’s not so far-fetched to suggest that Mars was a second home, or perhaps even a first home, for the life that now dwells upon the Earth. Perhaps, the idea is thrilling to entertain, Opportunity's journey to Mars was really a homecoming for life that began on Martian shores.

Last year, after Opportunity had been on Mars for 14 Earth years and traveled 28 miles, a particularly vicious dust storm began during the Martian southern spring. The atmosphere turned an ugly smoggy brown and it went dark at Meridiani. While the nuclear-powered Curiosity carried on at Gale Crater and InSight wound its way through deep space toward Mars, the Sun failed to reach Opportunity’s solar panels and her batteries ran down. She went silent on June 10, 2018.

For a long time there seemed to be hope that she would wake up and begin her mission of exploration and discovery once again. The controllers at JPL waited patiently. The dust began to settle from the atmosphere. They uploaded commands to the rover from the great radio antennas at Goldstone, Canberra, and Madrid. No response. It seems when the batteries drained the temperature of the rover fell below the point where the electronic brains and heart of the rover began to fail. The little plutonium heaters were insufficient to shut out the relentless cold of a world that did not birth them. Opportunity will not speak or move under her own power again.

Opportunity has been on Mars for half of my life. Both MER rovers, but especially Opportunity, have utterly transformed our collective human understanding of Mars and of the place of water and life in the solar system. Meanwhile my own life has changed beyond recognition. I went through high school, through college, and began working on the design of rockets to reach orbit, my passion from childhood. So many people and events touched my life in that time. I met the woman I married, who I share my life and children with. I met many friends, and sadly I’ve wandered away from many of them as the planets move and the years go by and the endless waves splash the dirty organic beaches of Earth.

In college I became friends with a woman who now works as a mission operations engineer at JPL. We shared a passion for the wonder and beauty of the universe beyond Earth. That shared passion brought us together for a few years of projects and get-togethers in Students for the Exploration and Development of Space at Texas A&M, then it sent us different directions as we pursued our interests separately. Today she signed the paperwork for the final planned attempt to contact Opportunity. There was a melancholy in this moment, knowing that the mission of so many years and dreams was coming to an end. But also, for me at least, there was a thrill to be this close to such an astonishing piece of history. My children will never know a Mars that wasn't warm and wet long ago, thanks in large part to these rovers. I hope that Keri Bean and the others at JPL who were the last people to say farewell shared in this feeling as well. The rest of humanity, marveling at the mysteries revealed, thanks you.

One day there will be living, laughing, breathing humans on Mars. For now we send our robotic emissaries, but one day we'll make the journey ourselves. One day some of those people will likely venture to the Spirit and Opportunity landing sites. Perhaps they will keep their distance, letting the rovers rest in the final locations their wheels and motors brought them. Perhaps they will gather them gently, clean the dust from their solar panels, and place them in a museum. Whatever they do, I’m sure they’ll look in wonder at what humans from the beginning of the 21^st Century were able to do, and the wonders that these little machines showed on the big world they explored.