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Subject: Tracks...
Time: 1:54:00 PM EDT
Author: stuartatk
Welcome to CARNIVAL OF SPACE readers!
Everyday now I can go online and, with just a click of a mouse, see new images from Mars, Saturn, comets, the Sun, asteroids, a dozen different places. Most prompt a “Hmm, nice” or at least a “Hmmm… okay…” from me, but sometimes an image flashes up on the screen that jumps out of my monitor, grabs me by the throat and shakes me like a rag doll.
Some are obvious – the classic “Earthrise” picture still takes my breath away, no matter how many times I see it, and I always feel a strange thrill whenever I see that timeless “Death Star” portrait of Mimas taken by Voyager – but others are classic in a more subtle way: Mimas looked sublime hanging in front of Saturn’s ring-shadow crossed, blue cloudtops… the Mars Reconaissance Orbiter’s view of Victoria Crater, with the rover Opportunity just visible near its rim as a blue-black dot… this week’s HD image of Earth taken by Kaguya, gleaming vivid blue and snow-white…
And then…
A couple of days ago an image flashed up on my screen and I literally froze as I looked at it...
It wasn’t anything anyone else would consider to be “special” or “amazing”; just a grainy, black and white picture of Opportunity’s tracks through the inches-high dust dune running around the edge of Victoria Crater, but it triggered something in me, a reaction, a response, that refused to go away. Just two notches in an undulating, close horizon, but it made my breath catch in my throat, because it occurred to me that that picture was the latest in a long line of images showing nothing less than Mankind’s progress and development – if not Evolution itself.
It is the latest in a chronological sequence of images showing The Tracks of Mankind.
This image is actually nothing to do with Mankind - obviously it pre-dates Man’s “arrival” on Earth by many millions of years. Those are dinosaur tracks, the footprints of “terrible lizards” pressed into the Earth over a hundred million years ago - but it is pretty amazing...!
The second image here shows part of an 80ft long trail of tracks laid down and preserved just – haha, just! - 3.7 million years ago. But this time the imprints aren’t of dinosaur footprints, but of footprints made by Australopithecus afarensis - primitive human beings, who lived in Tanzania. The story behind those tracks is incredible. Experts have figured out that almost 4 million years ago the nearby volcano Sadiman erupted, showering and blanketing the area with ash as fine as beach sand. Light rain falling on that layer of ash turned it into a mushy, wet cement like surface, across which birds, mammals and all kinds of life walked and hopped, each leaving its footprints, trails and tracks behind. A subsequent eruption by the volcano covered those trails and tracks with a new layer of ash, preserving them and sealing them until, millions of years later, erosion uncovered them again.
Some of the tracks were made by a pair of hominids, one large and one small, as they trekked across the wet ash. Some experts have even suggested that the trail made by the smaller of the two hominids bears signs suggesting that whoever left the footprints was weighed down on one side, suggesting they were made by a female carrying an infant hominid on or against her hip…
So, just take a moment to think about what you’re seeing in that second image in our sequence. It possibly shows tracks made by a family of early human beings, our deep time ancestors - a mother, father and child, walking together across a landscape covered with a layer of cloying, clogging wet ash as a volcano rumbled ominously in the background…
Almost 4 million years after those early humans left their tracks across the shaking and shuddering plains of Africa, humans had evolved into toolmakers, explorers and adventurers, and families by the thousand were making their way – and leaving their tracks - across the United States, not on foot but inside and on top of covered wagons, following a route that became known, famously, as The Oregon Trail. This thought-provoking image shows ruts in the rocky ground made by the passage of wagon after wagon after wagon across the state of Oregon, still clearly visible after almost two centuries.
Because of the distance involved, the duration of the trip and the logistical and engineering support needed, many people think that setting out on the Oregon Trail was the 17th century’s equivalent to embarking on a manned mission to Mars. Certainly settlers setting out on the Oregon Trail faced hardship and danger beyond their imagination. Sickness, starvation and accidents took their toll on the settlers; according to some sources, over a tenth of the emigrants died as they headed west. The Scout Kit Carson famously said: “The cowards never started and the weak died on the way”. Even so, in the two decades between 1840 and 1859 an estimated 52,000 people followed the Oregon Trail to settle there, although some historians say that perhaps five times that number decided to make their homes in Utah or California instead.
One day,after it has been explored by scientists and astronauts, families of settlers will head to Mars in their private or community spaceships to make a home there, and colonise Barsoom as Mankind has always dreamed of doing. Those spaceships will be the 21st – or 22nd? – century’s equivalent ofthe “prairie schooners”that crossed the US, rattling and rolling along the Oregon Trail, leaving their rutted tracks in the virgin ground of the United States of America…
It’s amazing to think that just eleven decades after the last covered wagon rolled to a shuddering halt at the end of the Oregon Trail, Man’s evolved monkey paws reached out for and touched the Moon. The Apollo missions are seen by many as the crowning glory of our species’ achievement, perhaps a glory that came before its time. With a phenomenal act of will and stubborn determination the United States landed not just one man, as Kennedy had ordered them to, but twelve men on the surface of the Moon, opening up a beach-head for the exploration of the solar system, and opening up a bold new frontier to beckon, test and be pushed back by the explorers, adventurers and settlers of future generations.
But we didn’t just leave historic bootprints on the Moon’s surface, like Buzz Aldrin’s famous footprint seen above. We left tracks on the Moon, too, as astronauts drove the almost impossibly fragile-looking lunar rover across its boulder-strewn, fire-ash grey landscape. This new, space age “prairie schooner” carried pairs of astronauts far from their landing sites, allowing them to explore rocks, craters and valleys far beyond safe walking distance. It wasthe lunar rover that allowed Apollo 15’s Dave Scott to find, and bring home, the most famous Apollo moon rock of all, the Genesis Rock, and without wind or rain or weather of any kind to disturb them the tracks left in the fine lunar dust by the three LRVs would look as crisp and sharp-edged today as they were when Apollo 17 blasted off from the Moon in 1972 at the end of Apollo 17.
… which brings me back to the present, and That Image showing the entry tracks of Opportunity into Victoria Crater.
But what’s the big deal? After all, we’ve all seen lots of images of Opportunity’s – and Spirit’s – tracks already. In the three and a half (Earth) years since their triumphant landing, each rover has looked back at and taken pictures of its tracks countless times. We’ve seen Spirit’s tracks meandering across the rusty floor of Gusev Crater, then up Husband Hill – and down again. We’ve also seen Opportunity’s tracks cutting across the vast Meridiani Plain, slicing through rippled dust dune after rippled dust dune, and occasionally getting stuck in one, and many of those images were, to be frank, a lot less boring and a lot more attractive than this latest one from Oppy.
Well, the difference is what the tracks represent – nothing less than the success and triumph of both Opportunity herself, and the Mars Exploration Rover mission as a whole. To make those tracks, “Oppy” had to climb out of her ‘cosmic hole in one’ landing site, Eagle Crater, then trek across the great Meridiani Plain just like one of those Prairie Cruisers rattling along the Oregon Trail. She survived becoming becalmed in the Great Dune Sea that stretches between Endurance Crater and her ultimate goal, Victoria Crater. Then, after reaching the huge crater’s edge, literally days before she was due to enter the crater and travel back in time to explore Mars geological past, the martian sky itself tried to kill her by covering the shrunken Sun with a howling dust storm and smothering Opportunity’s solar panels with potentially lethal fines. All she could do was stand there, frozen in place, and while her builders, controllers and supporters back on Earth could only cross their fingers and hope for the best, Oppy, unable to seek shelter from the wind and its waves of driving, lens-scratching dust grains, would have looked like one of those noble, storm-defying birds in the movie “March of The Penguins”…
… but the sky cleared, beams of weak sunlight fell on Oppy’s back again, and she started to drive again, each judder and shudder dislodging more dust and fines from her solar panels and wheels. She drove towards the edge of Duck Bay – her original arrival point at the crater all those months ago – and headed towards what looked like, at first glance, a Great Wall of Dust surrounding the edge of the crater like a barrier. In the end the Great Wall turned out to be just a matter of inches high, and Oppy simply drove through it, breaching it, and then headed slowly and carefully down into Victoria at last…
… and that’s where she is right now, studying and investigating a wide band of bright rock that runs around the crater’s inside like a ring of bubbles after a bath. The Mer team think that this bright rock is, in fact, the original surface of Mars, the original surface of Meridiani, which was buried by debris after Victoria Crater was formed.
That’s why that image struck a chord with me. It shows that Opportunity Did It. She made it into the crater, despite Mars doing its very best to stop her, and kill her.
Looking at the bigger picture though, just take a moment to think about what that feat actually means. It shows where we’ve come from – no, let’s be honest, and use the proper word; it show’s how we’ve evolved, from squat, hairy, ape-like creatures that left their footprints in a sloppy cement of volcanic ash and water, to thinking, reasoning, inquisitive creatures that built wagons of wood and cloth to carry them across the sweeping plains and jagged mountains of America, then built and drove shining metal rovers across the ash-grey, dusty plains of the Moon, beneath a Christmas tree bauble blue and white Earth…
… and now those apes are building and sending intelligent robots to other worlds – other worlds! – and driving them across the ruddy, rocky surface of Mars, sending them up mountains and into craters, to gain more knowledge, see more new sights, push back the frontier even more...
From Laetoli in Africa to the wide open plains of Barsoom, Man has now left his tracks for future generations to see and be inspired by – hopefully inspired enough to go on and make their own tracks. The next generation will make newrover tracks across the Moon, and possibly leave footprints and wheel marks across Mars. The generation after that might leave its tracks across the icy landscapes of Ganymede and Europa, and the one after that might, if they have the vision, leave its tracks across the icy methane rainkissed plains of Titan.
I don’t know about you, but that makes me very proud of how far we’ve come, and very proud of what we can achieve in the future - if we choose to follow that path, that new Oregon Trail out into the solar system and beyond.
So, look at these rover tracks on the edge of Victoria Crater and smile.
We did that.
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10/10/07 2:02 PM