FAR, FAR AWAY: The Worlds of Star Wars
Show Script –August 17, 2005 Charles Hayden Planetarium
In conjunction with exhibit Star Wars: Where Science Meets Imagination Developed by Museum of Science, Boston and Lucasfilm, LTD.
October 27, 2005 – April 30, 2006
(INTRO AND AUDIO TITLES)
Anthony, as himself:
Planet Earth. A small blue green world orbiting a star in the Milky Way Galaxy.
Here, filmmaker George Lucas imagined another galaxy, far far away, full of exotic planets, teeming with alien life. His motion picture, Star Wars: A New Hope brought to life worlds and creatures never before dreamt of, firing the imaginations of millions of moviegoers around the globe. But could worlds like those he imagined actually exist?
In 1995, we moved nearer to answering that question with an astonishing
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discovery. Two astronomers observed a star…that wobbled slightly. They hypothesized that this wobble was caused by the gravitational tug of an orbiting body. A planet. The first planet ever discovered outside our solar system orbiting a star like our Sun.
Astronomers now have several proven techniques to search for planets around other stars, which they call “exoplanets”. But our current technology limits what we can learn - these newfound worlds are so far away and so faint compared to the stars they orbit, they’re almost impossible to see. Spotting an exoplanet’s feeble light as it orbits a brilliant star is like trying to see a firefly next to a searchlight. Most often, their existence can only be inferred from the effects of their gravity, like the wobble.
To date, we have found over 150 exoplanets. And in time, we expect to find thousands more. So far, the worlds we've found probably can’t support any life. We suspect most of them are enormous -- but composed almost entirely of gas. In our own solar system, Jupiter and Saturn consist mostly of gas. And if these new planets are anything like the gas giants of our solar system, they offer no ground to walk on, no breathable air, and little hope for life as we know it.
But, with each passing year astronomers tease out smaller and smaller planets. As our technology improves, we may finally see a rocky, Earth sized world circling another star. Imagine… What might this alien world be like?
George Lucas grew up on a walnut Ranch in Modesto, California, watching
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reruns of Flash Gordon Serials. He tinkered with automobile engines, studied anthropology and mythology; and daydreamed that same question.
Might there be worlds out there like the ones in his imagination? Say, a lush green world, with rivers flashing silver through an emerald canopy of ancient trees, like the forest moon of Endor in Return of the Jedi? What about a planet like Hoth, a wind swept world of blizzards, pocked with icy caves, frigid, dangerous, but a perfect hiding place for a Rebel Army? Or Mustafar, where rivers of lava gouge canyons between jagged, obsidian mountains beneath a sky choked with volcanic ash? Could any galaxy contain such contrasts, such extremes? Absolutely. And for proof, we need look no further than our own planet.
The Earth has been changing and evolving since it first formed. Various stages of its evolution created landscapes and environments which resemble many of the exotic locations in the Star Wars films, and provide clues in the hunt for real exoplanets.
Four and a half billion years ago, our newly formed Earth was a molten mass, hot enough to melt rock. Huge meteorites blasted the surface with unimaginable force. Our planet’s first atmosphere was a dense, scorching fog of steaming water vapor, carbon dioxide, and poisonous gases like ammonia and methane. In this toxic stew, most life would die in an instant. But apart from that, and the lethal heat, our young Earth would have made a spectacular setting for the fictional Mustafar, the perfect place for a climactic light saber duel between a Jedi master and his former apprentice.
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Volcanic activity isn’t only found on Earth, but throughout our solar system, past and present. Mars is home to a number of now inactive volcanoes, including Olympus Mons, which towers three times higher than our own Mount Everest. Venus, and our Moon, have numerous smooth surfaces and channels through which lava may once have flowed.
In our solar system, the most violent volcanic world is Io, a moon of Jupiter. Relentlessly battered and stretched by the immense gravity of Jupiter and her sister moons, Io literally bursts with erupting volcanoes. Huge plumes of sulfur dioxide gas shoot almost two hundred miles above the moon’s surface, and then chill to a snow that falls back in cascades of brilliant crystals.
As the sulfur heats to different temperatures, it forms a rainbow of reds, yellows and blacks, which pool in vast, multicolored lakes on the everchanging surface.
With volcanic activity like this in our own solar system, it’s quite likely we’ll find worlds like the fictional Mustafar elsewhere in the galaxy.
Conditions on Earth did improve, given a billion years or so. Meteor impacts subsided, the planet cooled, and Earth’s crust hardened to form the sea floor and continents. The water vapor in the atmosphere condensed, forming oceans. And then our planet entered another, very different stage of its development. Earth was finally capable of supporting life. (maybe slightly modern music or SW Cantina Band)
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Soon microscopic organisms began to emerge. These creatures, called cyanobacteria, acted much as plants do today. They took in sunlight, absorbed carbon dioxide, and released oxygen. For two billion years, singlecelled life was the only life on Earth. As their numbers grew, these tiny creatures created Earth’s oxygen supply – the same oxygen you’re breathing right now. About half a billion years ago, more complex life forms emerged, and just a few hundred million years after that, creatures moved from the oceans to the dry land. Levels of oxygen and carbon dioxide in the air were far higher than we have today, allowing plant life to thrive. In turn, animal life grew larger and more diverse, until eventually, mighty dinosaurs roamed the lush, jungle-covered Earth.
Could there be an exoplanet now in a similar phase of development? Covered in foggy, fetid swamps, shrouded by thick gnarled trees, an ideal retreat for the last surviving Jedi master? Might there be a planet like Yoda’s Dagobah from The Empire Strikes Back? Or Kashyyyk, its jungle canopy home to the ferocious warrior species known as Wookiees? Or a forest world like the moon of Endor where the Empire finally went down in defeat?
Not all the worlds of Star Wars are lush and green. What of the ice planet Hoth? By day, Rebel soldiers might survive her frigid environment, but when darkness fell even native life forms would die from the cold without shelter. Could worlds like that possibly exist? In our own solar system, several moons and planets are completely enveloped in ice – among them, Saturn’s moon Enceladus, Jupiter’s moon Europa, and the planet Pluto.
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Still, in one significant way, these known worlds differ from the unforgiving landscape of Hoth. The frozen moons and planets of our solar system have no breathable air. On these worlds, it’s highly unlikely that animals, such as the Tauntauns from The Empire Strikes Back would ever evolve, let alone grow large enough to serve as improvised sleeping bags.
But Earth has an atmosphere, and has endured at least two global ice ages that transformed our blue planet into a wintry white ball almost as treacherous as Hoth. (In the clear)
How did it happen? (music change)
Geologists aren’t sure, but one possibility is that a series of extremely snowy winters and cool summers spiraled out of control. While a dark green and blue Earth absorbs heat from the Sun, white snow reflects that sunlight away. More snow on the ground means less heat stays on the Earth’s surface. As the global temperatures drop, snow piles higher, more sunlight is reflected, triggering an ice age. The entire planet plunges into a deep freeze. During the coldest moments of Earth’s past, ice reached as far as the equator and the oceans froze solid, almost as deep as the sea floor. We call this phenomenon Snowball Earth.
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Eventually, volcanic eruptions helped our planet recover from this frozen state. Carbon dioxide from the Earth’s venting volcanoes formed clouds that trapped heat and prevented it from radiating back into space. The ice gradually melted, and the few creatures that had survived on the sea floor slowly repopulated the oceans. Since then, Earth has experienced other ice ages, but none as severe as Snowball Earth.
If other planetary systems are anything like our own, we should find icy worlds throughout the galaxy, some of which might even have an environment able to support a few extremely hardy species or safeguard the daring Rebels.
Today, our Earth is rich with multiple climates, – some hot, some cold, some wet, some dry; much like the Star Wars planet Naboo with its rolling plains, wooded hills, and swampy lakes above vast, subterranean oceans. The varied climates found on our very real Earth and the imaginary Naboo produce a variety of conditions which help shape their landscapes. More importantly, both worlds have breathable air.
But how exactly will astronomers find these planets? Scientists have planned several space missions designed to search for Earth-sized worlds orbiting nearby stars. Among them are the Terrestrial Planet Finder missions. Developed by NASA, they’ll consist of two separate observatories in space, each designed to find Earth-like planets and study the gases in their atmospheres. Astronomers are eager to find planets with atmospheres that match our own, since they will be more likely to support life.
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Might these space-based observatories discover a planet like Kamino featured in Attack of the Clones? A planet completely submerged in water, thunder and lighting lashing her seas into mountainous waves? Quite possibly. Earth itself has the potential to become a water world. Much of our planet’s present water supply is trapped in the polar ice caps. If Earth warmed enough to melt them, sea level would rise more than 500 feet. Earth’s coastal cities would be submerged. Imagine: Tokyo, London, Los Angeles, and Boston, sunk beneath the waves like the fabled Atlantis. Could this be Earth’s future?
Or might our world one day be more like Tatooine, home planet to the most central characters in the entire Star Wars saga? A harsh land of desolate sand dunes, strange rock formations, barren and dry? There’s a real desert planet practically in our neighborhood, astronomically speaking. Mars. Our red neighbor is much like Tatooine -- a desert wasteland, subject to violent dust storms which blanket the whole planet in a choking haze.
Conditions on Mars weren’t always so bleak. When the NASA Rovers, Spirit and Opportunity, arrived on the planet in 2004, these two remotecontrolled dune buggies found evidence that billions of years ago Mars had rivers, and streams, and lakes. We don’t know how or why, but that water is now gone, either evaporated away into space or buried below the planet’s dusty soil. All that’s left are traces of water in its atmosphere. Is the fate of Mars foreshadowing some distant future in Earth’s evolution?
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What about other Star Wars worlds — the ones that don’t quite resemble any planets or moons in our solar system? It’s very possible that exoplanets like these also exist, somewhere. Take for example, Geonosis, the rocky red planet in Attack of the Clones. Rings of rubble surround the barren world. But how could rings such as these be formed? Perhaps after two moons collide near a planet. Or when a large moon wanders too close and is ripped apart by the planet’s gravity. The debris from either catastrophe might settle into thin, circular systems of rings. Observing a ringed world from a distance could be easy. If the rings are icy and reflective, like those of Saturn, they shine brightly in the darkness of space.
We may not be the only life forms seeking to discover new worlds. Perhaps civilizations on other planets have their own equivalent of NASA’s Terrestrial Planet Finder Missions. Imagine a world like Coruscant; home to the powerful Jedi Council and Galactic Senate. A world completely encased in a single, globe-spanning city. Such an advanced metropolis could be broadcasting radio signals into space. And we, so distant from the source of these signals, could listen for them. In fact, we are listening. Gigantic radio telescopes are trained on the far reaches of space. If the citizens of a Coruscant-type world are broadcasting, it is exciting to think one day, we might hear them.
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While we can’t know what Earth will be like in the next few thousand years, we do know it will continue to change, and so we will have to adapt to survive. Perhaps we’ll realize the dream of reaching other worlds. We are taking our first steps even now. Plans are underway to send humans on a exploratory mission to Mars. One day, we may be able to live there. But first, we’ll need to find ways of surviving long periods in an alien environment. That means making air to breathe and water to drink.
In Star Wars, George Lucas solved this problem by creating an entire profession. Luke Skywalker’s Uncle Owen and Aunt Beru were “moisture farmers.” They used devices called vaporators to collect traces of water from the air – water that could then be used for drinking or irrigating crops.
Other life forms of the Star Wars Universe used technology to manage their environments. The Wookiees of Kashyyyk and the Ewoks of Endor built villages in the trees. The Gungans of Naboo designed enclosed cities providing a hospitable home deep beneath the planet’s oceans. The insect life forms on Geonosis used their rocky planet’s resources to build hive-like dwellings that stretched to the sky. On Hoth, the Rebel Alliance built their Echo Base within its vast system of ice caverns, harnessing heat from the planet’s core for power. The cloners of Kamino lived in dry, pod-like structures, perched on tall pillars above the turbulence of their ocean world. One day, humans may live on exotic worlds like these, providing we can meet the challenges of such environments.
But while technology can make hostile worlds habitable, it could easily turn… less friendly.
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(Death Star blows up Alderaan -- clip from movie)
It’s highly unlikely that you’ll wake up tomorrow and see the Death Star looming in the sky, but the threat of being hit by an object from outer space does exist. Most scientists believe that an impact by a large asteroid helped to kill off the dinosaurs 65 million years ago. Are humans threatened by a similar fate? What does it take to destroy an entire planet?
There is scattered debris in the solar system, and a surprisingly small object could cause large-scale destruction if it were to hit Earth. If we collided with an asteroid only the size of a football stadium, any city it hit would be devastated. Even so, humans elsewhere on the planet could survive.
But could an even larger object, say a huge comet or vast asteroid, obliterate our whole planet? It's nearly impossible. It would take an impact from an object more than half the size of Earth itself to disintegrate it completely, an extremely unlikely event today.
Some scientists believe that an enormous impact already occurred, shortly after our planet’s formation, at a time when the evolving solar system was still churning with huge rocky debris. There is evidence that an object the size of Mars may once have slammed into Earth. If this collision did happen, it would have nearly destroyed our planet. But Earth would have recovered, and over time, gravity could have pulled the left-over debris together, perhaps forming the Moon.
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Our planet seems tenacious, able to withstand almost any catastrophe, and the life that graces it can thrive in the most extreme conditions! We have discovered creatures living in places we would have thought impossible -
…at the ocean bottom, tiny organisms totally isolated from sunlight thrive on heat and nutrients gushing from hot vents beneath the ocean floor…
…in frigid Antarctica, they inhabit windswept valleys and lakes buried deep under the ice…
…and incredibly, miles deep within the Earth itself, they literally live off the barren rock around them.
The first life on our planet emerged billions of years ago. Since then, it has survived meteor impacts and global ice ages. Today, it’s everywhere we look—in every ocean, under every rock, among the leaves of every tree. (Pause) Life flourishes all around us.
Knowing this, we can’t help but imagine—where else in the universe does life exist?
What kind of life might it be? Familiar and recognizable? Or something new, beyond our wildest dreams? The same insatiable curiosity inspires the quests of artists and engineers, filmmakers and scientists.
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With each new exoplanet we discover, we are reminded that we may not be alone in our galaxy. And, if we someday find a rocky, Earth-like planet orbiting a Sun-like star, the worlds of our imaginations might become worlds of reality, and the Star Wars galaxy imagined by George Lucas might turn out not to be so very far, far, away.
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