George's Cosmic Treasure Hunt

by Lucy Hawking

  “Then I’ll pay for him to go,” retorted Gran.

  “Oh, you heard that, did you?” said George’s dad, who was still scribbling away in the notebook.

  “I lip-read,” said Gran hastily. “I can’t hear a thing. I’m deaf, you know!”

  You can’t afford to send George to America! George’s mom wrote in her notepad.

  “Don’t you tell me what I can and can’t do!” said Gran. “I’ve got pots of money, all hidden under the floorboards. More than I know how to spend. And if you silly people won’t let him go by himself, then I’ll fly out with him. I’ve got some friends in Florida whom I haven’t seen in years.” She grinned at George. “What do you say, George?” she asked.

  With a huge smile on his face, George nodded at her so many times, his head looked like it might fall off. But then he turned to his parents to see how they were taking it. He couldn’t believe they would agree to any of this, especially since it meant traveling on an airplane—something his mom and dad didn’t approve of, in theory.

  But Gran had thought of that problem already. “You know,” she said airily, “I don’t see why it should be just George and I who get to go away. After all, Terence, you and Daisy haven’t been anywhere exciting for a very long time. There must be somewhere you’d like to go—somewhere in the world you could do some good; somewhere you could really make a difference, if only you had the time and the ticket to get there.”

  George’s dad gasped, and George realized that clever Gran had spoken right to his heart.

  “Isn’t there something you’d love to do?” she persisted.

  Her son wasn’t looking angry anymore but hopeful instead. “You know,” he said to George’s mom, “if George did go to Florida for summer vacation and Mother would help us out with the airfares, it would mean that we could go on that other trip ourselves—the eco-mission to the South Pacific.”

  She looked thoughtful. “I suppose we could,” she mused. “I’m sure Eric and Susan would take good care of George.”

  “Excellent!” piped up Gran, intent on closing the deal before anyone could change their minds. “It’s a plan. George goes to Florida and you can have a vacation—I mean, save the world,” she corrected herself quickly. “I’ll buy the tickets for everyone and we’ll be off.”

  George’s dad shook his head at his mother. “Sometimes I think you only hear what you want to hear.”

  Gran just smiled regretfully and pointed to her ears. “Didn’t catch that,” she said firmly. “Not a word.”

  George felt the laughter bubbling up inside him. Because of Gran, he might be going to America! Where Annie was waiting for him with some hot news about her discovery. He felt a bit guilty about his mom and dad. They thought they were sending him off for a nice, safe, quiet vacation in a different country. But George knew enough about Annie’s way of working to suspect it was going to be anything but safe and quiet. And she’d mentioned the space suits in her message—the ones they’d worn to fly around the Solar System. It must mean she had uncovered a secret that had to do with space, and she wanted him to travel out there with her once more. He held his breath while he waited for his mom to speak.

  “All right, then,” she said, after the longest pause. “If Gran is offering to take you to Florida, and Eric and Susan will meet you the minute your plane touches down and take care of you the whole time, I suppose I have to say yes!”

  “YES!” said George, punching the air. “Thanks, Mom, thanks, Dad, thanks, Gran. Better go pack!” With that, like a little whirlwind, he was gone.

  It was so exciting to be packing to go on a journey rather than watching other people fill their suitcases. George had no idea what to take with him so he just threw things around his room for a while and made an incredible mess.

  He didn’t know much about America, just what he’d seen on TV shows when he’d been at friends’ houses. That didn’t give him much of a clue to what he might need in Florida. A skateboard? Some cool clothes? He didn’t have either. He packed some of his books and clothes and put his precious copy of The User’s Guide to the Universe in his schoolbag, which he was using as his carry-on luggage for the plane. As for packing for a trip into space, George knew that astronauts only took a change of clothes and some chocolate with them, but then they went up in spaceships, and he doubted even Annie had managed to arrange for one of them.

  As George got ready to leave, so did his parents. They had decided they would go on the eco-mission while he was in the United States. They were going to join a ship in the South Pacific that was helping some islanders whose lives were being threatened by rising seawater.

  “We’ll be in touch as often as we can from the sinking islands—by e-mail or phone,” George’s dad told him. “Find out how you’re doing. Eric and Susan have promised to look after you. And Gran”—he sighed—“will be nearby, if you need her.” Even Freddy the pig got to take a vacation—he was going to spend the summer at a local children’s farm.

  George couldn’t sleep at all the night before the flight. He was off to America to see his best friend and maybe, just maybe, go out into space again. He’d flown around the Solar System before, but he’d never actually been on an airplane, so that was exciting too. Before, he’d been far away in outer space, but this time he would be flying through the Earth’s atmosphere. He would be traveling through the part where the sky is still blue, before it turns to the black of space.

  On the plane, he looked out of the window at the white, fluffy clouds below. Above them, he could see the Sun, the star at the center of our Solar System, radiating down heat and energy. Below was his planet, which he saw in snatches when the clouds parted.

  Gran slept for most of the journey, giving out tiny gentle whooshes of air, just like Freddy did when he was dozing. While she slept, George got out The User’s Guide to the Universe and read about another voyage—this one not just across our planet but across our whole Universe.

  * * *

  THE USER’S GUIDE TO THE UNIVERSE

  A VOYAGE ACROSS THE UNIVERSE

  We will now go on a voyage across the Universe.

  Before setting out we must understand what we mean by the terms voyage and universe. The word universe literally means “everything that exists.” However, the history of astronomy might be regarded as a sequence of steps, at each of which the Universe has appeared to get bigger. So what we mean by “everything” has changed.

  Nowadays most cosmologists accept the Big Bang theory, according to which the Universe started in a state of great compression around fourteen billion years ago. This means that the farthest we can see is the distance that light has traveled since the Big Bang. This defines the size of the observable Universe.

  So what is meant by a voyage? First we must distinguish between peering across the Universe and traveling across it. Peering is what astronomers do and, as we will see, involves looking back in time. Traveling is what astronauts do and involves crossing space. This also involves another kind of voyage. For as we travel from the Earth to the edge of the observable Universe, we are essentially retracing the history of human thought about the scale of the Universe. We will now discuss these three journeys.

  The Voyage Back Through Time

  The information astronomers receive comes from electromagnetic waves that travel at the speed of light (186,000 miles per second). This is very fast, but it is finite and astronomers often measure distance by the equivalent light travel time. Light takes several minutes to reach us from the Sun, for instance, but years from the nearest star, millions of years from the nearest big galaxy (Andromeda), and many billions of years from the most distant galaxies.

  This means that as one peers across greater distances, one is also looking farther into the past. For example, if we observe a galaxy ten million light-years away, we are seeing it as it was ten million years ago. A voyage across the Universe in this sense is therefore not only a journey through space; it is also a journey back through time—right ba
ck to the Big Bang itself.

  We cannot actually observe all the way back to the Big Bang. The early Universe was so hot that it formed a fog of particles that we cannot see through. As the Universe expanded, it cooled and the fog lifted about four hundred thousand years after the Big Bang. However, we can still use our theories to speculate what the Universe was like before then. Since the density and temperature increase as we go back in time, our speculation depends on our theories of high energy physics, but we now have a fairly complete picture of the history of the Universe.

  One might expect that our voyage back through time would end at the Big Bang. However, scientists are now trying to understand the physics of creation itself and any mechanism that can produce our Universe could, in principle, generate others. For example, some people believe the Universe undergoes cycles of expansion and re-collapse, giving us universes strung out in time. Others think that our Universe is just one of many “bubbles” spread out in space. These are variants of what is called the multiverse proposal.

  The Voyage Across Space

  Physically traveling across the Universe is much more challenging because of the time it would take. Einstein’s special theory of relativity (1905) suggests that no spaceship could travel faster than the speed of light. This means it would take at least one hundred thousand years to cross the Galaxy and ten billion years to cross the Universe—at least as judged by someone who stays on Earth. But special relativity also predicts that time flows more slowly for moving observers, so the trip could be much quicker for the astronauts themselves. Indeed, if one could travel at the speed of light, no time at all would pass!

  No spaceship can travel as fast as light, but one could still approach this maximum speed. The time experienced would then be much shorter than that on Earth. For example, a journey across the Galaxy at nearly the speed of light would seem to take only thirty years, while much more time would have passed on Earth. One could therefore return to Earth in one’s own lifetime, although one’s friends would have died long ago. If one continued to accelerate beyond the Galaxy for a century, one could, in principle, travel to the edge of the currently observable Universe!

  Einstein’s general theory of relativity (1915) could allow even more exotic possibilities. For example, maybe astronauts could one day use wormholes or space warp effects—just like in Star Trek and other popular science-fiction series—to make these journeys even faster and get home again without losing any friends. But this is all very speculative.

  The Voyage Through the History of Human Thought

  To the ancient Greeks, the Earth (geos) was the center of the Universe (cosmos), with the planets, the Sun (helios), and the stars being relatively close. This geocentric view was demolished in the sixteenth century, when Copernicus showed that the Earth and other planets move around the Sun. However, this heliocentric picture did not last very long. Several decades later, Galileo used his newly invented telescope to show that the Milky Way—then known only as a band of light in the sky—consists of numerous stars like the Sun. This discovery not only diminished the status of the Sun, it also vastly increased the size of the known Universe.

  By the eighteenth century it was accepted that the Milky Way is a disk of stars (the Galaxy) held together by gravity. However, most astronomers still assumed that the Milky Way comprised the whole Universe, and this galactocentric (galactos = milk) view persisted well into the twentieth century. Then, in 1924, Edwin Hubble measured the distance to our nearest neighboring galaxy (Andromeda) and showed that it had to be well outside the Milky Way. Another shift in the size of the Universe!

  Within a few more years, Hubble had obtained data on several dozen nearby galaxies, which showed that they are all moving away from us at a speed that is proportional to their distance from us. The easiest way to picture this is to think of space itself as expanding, just like the surface of an inflating balloon onto which the galaxies are painted. This expansion is known as Hubble’s Law, and it has now been shown to apply up to distances of tens of billions of light-years, a region containing hundreds of billions of galaxies. Yet another huge shift of scale!

  The cosmocentric view regards this as the final shift in the size of the Universe. This is because the cosmicos expansion means that as one goes back in time the galaxies get closer together and eventually merge. Before that, the density just continues to increase—back to the Big Bang fourteen billion years ago—and we can never see beyond the distance traveled by light since then. However, recently there has been an interesting observational development. Although one expects the expansion of the Universe to slow down because of gravity, current observations suggest that it is actually accelerating. Theories to explain this suggest that our observable Universe could be a part of a much larger “bubble.” And this bubble could itself be just one of many bubbles, as in the multiverse proposal!!

  What Next?

  So the end point of all three of our journeys—the first back through time, the second across space, and the third retracing the history of human thought—is the same: those unobservable universes that can only be glimpsed through theories and visited in our minds!

  I wonder what tomorrow’s astronomers will discover…

  Bernard

  * * *

  When the plane landed, George and Gran joined the line to get through immigration and customs. Eric and Annie were waiting in the arrivals area. Annie shrieked and jumped up and down on the other side of the barrier as soon as she saw him.

  “George!” she hollered. “George!” She ducked under the rail and grabbed him. She was taller and more tan than he remembered. She hugged him and whispered in his ear, “It is sooooo good you are here! Can’t tell you now, but we are in an emergency! But remember, shush! Say nothing.” She took his cart and careered off with it toward Eric. Gran and George hurried after her.

  George had a shock when he saw Eric. He looked so tired, with some strands of white in his dark hair. But he smiled when he saw George, and his face lit up just like it used to.

  They said their hellos, and Gran shook hands with Eric and got him to write down comments in her notebook. Then she gave him an envelope marked George’s Emergency Fund, hugged her grandson, grinned at Annie, and went off to greet her friends, who had come to the airport to meet her. “A bunch of old rogues and rebels from my past, who live near Eric and Susan,” she had told George. “Nice chance for us to relive some of our hijinks.”

  But the people who came to pick up Gran were so old and wobbly-looking, George couldn’t imagine them ever being young, let alone having an adventure. Gran tottered off into the distance with them, and he felt his stomach shrink as he watched her leave. It seemed very big and bright here in America—everything was much shinier and larger and louder than it was at home. A wave of homesickness struck him. But not for long.

  A smaller boy with thick glasses and a very peculiar hairstyle had appeared from behind Eric.

  “Greetings, George,” he said earnestly. “Annie”—he shot her a look of total disgust—“has told me all about you. I have been eagerly anticipating interfacing with you. You sound a most interesting person.”

  “Back off, Emmett,” said Annie fiercely. “George is my friend, and he’s come to see me, not you.”

  “George, this is Emmett,” Eric told him calmly, while Annie glared at Emmett and Emmett looked away with pursed lips. “He is the son of one of my friends. Emmett is staying with us for a while this summer.”

  “He’s the son of doom, more likely,” Annie whispered in George’s ear.

  Emmett snuck around to George’s other side and hissed in his other ear, “The girl humanoid is a total moron.”

  “As maybe you can tell,” continued Eric lightly, “there’s been a small falling-out between these two.”

  “I told him not to touch my Girl’s World action doll!” Annie exploded. “And now it only speaks Klingon.”

  “I didn’t ask her to cut my hair,” Emmett bleated. “And now I look stup
id.”

  “You looked stupid before,” muttered Annie.

  “Better to speak Klingon than just garbage like you,” retorted Emmett. His big eyes, magnified by his glasses, looked very shiny.

  “George has had a long journey,” said Eric firmly. “So we are going to take him to the car and drive home, and everyone is going to be nice to everyone else. Do you hear me?” He sounded quite stern.

  “Yes!” said George.

  “It’s all right, George,” said Eric. “You’re always nice. It’s the other two I’m worried about.”

  Chapter 4

  Eric drove them to the big white wooden house where his family now lived. The sun was beating down from the perfectly blue sky, and the heat rose up from the ground to smack George in the face as he got out of the car. Annie scrambled out after him. “Come on,” she said as Eric unloaded George’s bag from the trunk. “We’ve got work to do. Follow me.” She took him around to the back of the house, where a huge tree shaded a veranda with a table and chairs on it.

  “Up the tree!” Annie instructed him. “It’s the only place we can talk!” She shinned up to a large overhanging branch. George slowly clambered after her. Susan had come out onto the veranda, carrying a tray. She stood underneath Annie and George, with Emmett close behind her.

  “Hello, George!” she called up into the tree. “It’s nice to see you! Even if I can’t actually see you.”

  “Hello, Susan,” George called back. “Thanks for inviting me.”

  “Annie, don’t you think George might like a rest? And something to eat and drink after his journey?”

  “Give it to the tree,” said Annie, sticking her head out through the papery green-and-white leaves. She reached down with an arm and grabbed a juice box, which she handed back to George, and then a load of cookies.

  “Okay, we’re good now!” she sang. “Bye, other people! You can vamoose!”

  Emmett just stood there, looking longingly up into the tree.