Read George's Cosmic Treasure Hunt Online
Authors: Lucy Hawking
E
eew!” said Annie, shielding her eyes with her arm as they stepped through the portal from Titan onto the planet Cosmos had found for them in orbit around the star Alpha Centauri B. Fortunately, after a few seconds, the special glass in her space helmet visor darkened and her vision started coming back.
“Wow! It's bright,” said George, stepping through after her. This time they thought they were better prepared than when they had landed on Mars and Titan. They had gotten out the emergency rope and the metal pegs that came with their space suits, ready to tether themselves to the surface of their new planet. But when they stepped through the doorway, they found that for once they didn't float off. Instead, they felt much heavier than they did on Earth.
They could still walk, but it was an effort to pick up each leg to move forward.
“Oof!” said Annie, dropping the rope and the pegs. “I feel like I'm being squished.” It was as though someone was pushing her toward the bleached ground.
“More gravity!” said George. “We must be on a planet similar to Earth but with a greater mass, so we feel the gravity more strongly than we would at home. But it can't be that much greater or we'd be crushed by now.”
“I'm going to sit down,” puffed Annie. “I'm really tired.”
“No! Don't!” said George. “You might never get up again. You shouldn't sit down, Annie, or we'll never get away from here.”
Annie groaned and leaned on him. She felt like a ton, and George staggered to stay upright and hold on to her at the same time.
“Annie, we've got to find the next clue and leave,” he said urgently. “There's too much gravity here for usâwe weren't built to exist in conditions like these. If we were ants, we'd be okay. But we're too big for high-gravity places. And it's too shiny. It hurts my eyes.”
Where Marsâand certainly Titanâhad been much darker than the Earth, this new planet was blindingly bright. Even with the dark space visors protecting their eyes like superstrength sunglasses, it was still difficult to see. “Don't look directly at the sun,” warned
George. “It's even brighter than our Sun at home.”
Not that there was much to look at. Around them stretched miles of bald rock, baking in the brilliant light beaming down on this heavy, hot planet. George gazed around anxiously, looking for some sign that would lead them to the fourth clue.
“Whassâ¦thatâ¦overâ¦there?” Annie, who was now leaning on him entirely, flapped an arm in one direction. Her speech had become very slow and slurred.
George shook her. “Annie! Wake up! Wake up!” The light and the weight of this weird planet seemed to be drugging her. He tried to call Cosmos or Emmett. The first time he got a busy signal, the second, a recorded message saying: “
Your call is important to us. Press the pound key plus one to be put through toâ
” But then he was cut off.
Annie flopped onto him. She was so heavy on this planet that it was like trying to carry a baby elephant. George stood there, Annie's head on his shoulder and his arms around her. He started to feel really scared. He imagined that in years to come, when the first interstellar travellers made the journey to this unnamed planet in orbit around one of the nearest stars to Earth, they might find the scorched remains of two human children, frazzled and boiled into fragments on the parched surface. Somewhat dazed himself, he pictured them leaping off their spaceship to claim this new planet, only to find that two kids had once made the four-light-year journey to this infernal place, only to perish under its burning star.
But just as he was giving up hope and starting to sag toward the ground, the light in the sky began to dim a little. It was changing from brilliant white to a softer yellow.
“Look, Annie!” he said, shaking her in his arms. “The sun's going down! You're going to be okay! Just hold on for a few minutes more. It's moving across the sky pretty quicklyâwell, quicker than the Sun back home on Earth, anyway. Once it goes down, we'll be able to cool off and find the clue.”
“Huh?” said Annie blearily. She raised her head from his shoulder and stared out behind him. “But it's not going down! It's coming upâ¦. It's really pretty,” she went on dreamily. “Bright shiny star rising in the sky⦔
“Annie, it's not going up!” said George, who thought she must be hallucinating. “Concentrate! The sun is going down, not up!” The light around them was dimming gently.
“Don't be silly!” Annie sounded annoyed, her voice slightly stronger. George felt relievedâif she could get mad at him, then she was definitely feeling better. “I know up from down, and I tell you it's going up!”
They moved apart by a few inches and stood staring over each other's shoulders.
“It's that way,” said Annie, pointing. “Up!”
“No, it's over there!” said George. “Down!”
“Turn around,” ordered Annie.
George turned around very slowlyâit wasn't possible to move fast on the high-gravity planetâand saw she was right. There was a small bright sun in the sky behind him, rising over the rocky planet. It didn't give the same glaring light as the sun setting on the other side of the planet, but it shone a gentle beam on them, meaning that it would not often be dark on this bright, barren planet.
“Of course! We're in a binary star system, just like it showed us in the clue! This planet has two suns!” said George. “I'm sure I've read about this system on the Net. One sun is bigger than the otherâthat one setting must be Alpha B, the star this planet orbits. It looks bigger because we're closer to it. And the other one must be Alpha A, the other star in the Centauri system. Alpha A is actually larger, but we're farther away from it.”
Now that the light was growing softer, they could make out more of the landscape around them. Quite nearby they saw the lip of a huge hole in the ground.
“Let's go and have a look in there,” said Annie.
“Becauseâ¦?” questioned George.
“There isn't anywhere else to look!” She shrugged. “And maybe there's another clue down there. On both Mars and Titan, Cosmos sent us really close to each new clue. Have you got any better suggestions?” She seemed back to her usual difficult self.
“Nope,” said George. He tried calling Emmett again but just got the busy signal again.
“Come on,” said Annie, “but I'm not walking.” She dropped to her hands and knees and started to crawl toward the crater.
George tried to walk, but it was so difficult and slow. He felt like the Tin Man in
The Wizard of Oz
, having to throw each leg forward in order to move. So he too got down on his hands and knees and followed Annie, who was now peering over the edge to see what lay at the bottom.
“There's nothing there,” she said in disappointment, looking into the gaping empty crater formed by a collision with a comet or an asteroid.
George wriggled up beside her. “Then where will we find the next clâ?” he started to say. But he stopped. Because just then, at the very bottom of the huge crater, they saw something they definitely weren't expecting. Faintly, but getting more solid by the second, they saw the outline of a doorway. And at the same moment as one space boot and then another stepped through it, the transmission device in George's helmet buzzed into life.
“George!” he heard. “This is your grandmother speaking. Eric is on the way!”
A
t the bottom of the crater, Eric stepped quickly through the portal and promptly fell flat on his face. He had prepared his telling-off speech to the kids while he was getting ready to walk through Cosmos's doorway. But once he reached the distant planet, all he came out with was “Nrrgghh!”
“Dad!” cried Annie from the top of the crater, and burst into tears inside her space helmet. She no longer cared whether he was going to be mad at her. She just felt overjoyed to see him. She slithered over the crater's lip and wriggled down toward him on her tummy. As Eric rolled over onto his back, Annie crashed into him and gave him a great big hug.
“Dad!” she sobbed. “It's so nasty here! I don't like this planet.”
Eric gave a huge sigh that Emmett and Mabel heard many millions of miles away on planet Earth, and he decided to save his speech about kids who traveled through space by themselves when they shouldn't for another time. Instead, he hugged Annie.
George's gran had no such reservations. “George!” she said sternly over the link from Earth. “I can't believe you roped me into this dangerous scheme without telling me! I'm very angry that you didn't see fit to properly inform me why you wanted to come to Americaâ¦.” She went on and on, and George wished he could turn down the volume, as Emmett had done with Cosmos. But then he looked into the crater and saw Eric beckoning George to come and join them.
“Sorry, Gran!” said George. “I have to go! We'll talk later.” And he slid down the side of the enormous hole to join Eric and Annie, ending up in a group hug in space suits at the bottom of the crater on an unnamed planet orbiting Alpha B in the Alpha Centauri star system.
“I've got to close down the portal for a few minutes,” came Emmett's voice. “I can't hold the portal and do all the other things I need to with Cosmos. So don't panic when the doorway vanishes. I'll get it back to you right away.”
The portal doorway became translucent and started to fade away. George, Annie, and Eric lay back against the curved surface of the crater's wall and gazed at Alpha A, moving across the clear, dark blue sky.
“So, George and Annie,” said Eric as they lay on either side of him. “Here we all are, together, once again. Lost in space, once again.” By now, the portal had completely disappeared.
“Can we go home now?” sniffed Annie. “I've had enough of this.”
“Soon, very soon,” said Eric calmly. “Just as soon as Emmett gets the reverse portal working again.”
“What!” exclaimed George, trying to sit up but finding he didn't have the strength left to fight gravity. He lay back down again. “You mean we can't go back to Earth?”
“I'm afraid not,” said Eric quietly. “Cosmos is having some problems, but Emmett will sort them out. I wouldn't have left him in charge if I weren't sure he was the best person for the job. He's already done things with Cosmos I couldn't even dream of.”
“You mean you came here to find us even though you knew we might not be able to get back?” said Annie. “That we might be stuck here forever?”
“Of course I did,” said Eric. “I couldn't leave you out here by yourselves, could I?”
“Oh, Dad!” cried Annie. “I'm so sorry! Now we're going to be burned to a crisp on this horrible planet, and it's all my fault!”
“Don't be silly, Annie. This isn't your fault, and it's going to be okay! We're not going to stay long enough for that to happen,” said Eric firmly. “But we do need to leave here before Alpha B rises again. Even with our
space suits, it's too hot for us on this planet because it lies too close to its starâthat's why there is no water and no life here. But we'll go somewhere else. Somewhere nicer.”
“So Cosmos can still send us farther out?” said George hopefully. He didn't want to see the blinding light of Alpha B ever again in his whole life.
“Yes,” said Eric, more confidently than he felt. “Sometimes we have to go far, far away in order to be able to get back. So don't worry if it feels like we are traveling in the wrong direction. Think of it as gaining perspective.”
“How soon will Alpha B rise again?” asked George.
“I don't know for certain,” said Eric, “but we must be gone before its dawn.”
“Where are we going?” said Annie.
“Another planet,” Eric told her. “Cosmos is looking for another planet to send us to. Emmett tells me that you have been following clues across the Universeâin a sort of cosmic treasure hunt.”
“Um, yes,” George admitted. “We kept going because in each place we found another clue that sent us to a new location.”
“And you came here because the clue you found on Titan told you to go to a binary star system with a planet in orbit around one of the stars?”
“We thought we'd been really smart,” said Annie sadly.
“Oh you have!” said Eric. “All three of you. Emmett believes that the clues are taking you on a hunt for signs of life in the Universe. If he's right, then we need to find a planet in what we call the Goldilocks Zone of its star. That means a planet that is not too hot, not too cold, but just right.”
“Oh!” said George. “I seeâthis planet is too hot! So we know this isn't the right planet.”
“And I can think of another reason to suspect this isn't the right place. How many stars did the clue show?” asked Eric.
“Two,” said George.
“Here,” said Eric, “there are three. That fainter star, the one you can only just see over thereâthat's Proxima Centauri, so called because it's the closest star to Earth. So this is a
triple
system.”
“Oh no! Wrong planet, wrong star system,” said George. “What do we do now?”
“So, do you believe us now, about the clues and the messages?” interrupted Annie.
“I do, darling,” admitted Eric. “And I'm so sorry. I'm sure those messages were left for me, not for you. And if I could send you back to Earth right this second, I would. But I can't do that and I can't leave you here. So I think we're going to have to finish the cosmic treasure hunt together. Are you with me?”
Annie moved closer to him. “I am,” she said, “very definitely.”
ALPHA CENTAURI
At just over four light-years away, Alpha Centauri is the closest star system to our Sun. In the night sky it looks like just one star, but is, in fact, a triplet. Two Sun-like stars, Alpha Centauri A and Alpha Centauri Bâseparated by around twenty-three times the distance between the Earth and the Sunâorbit a common center about once every eighty years. There is a third, fainter star in the system, Proxima Centauri, which orbits the other two but at a huge distance from them. Proxima is the nearest of the three to us.
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Alpha A is a yellow star and very similar to our Sun but brighter and slightly more massive.
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Alpha B is an orange star, slightly cooler and a bit less massive than our Sun. It is thought that the Alpha Centauri system formed around one thousand million years before our Solar System. Both Alpha A and Alpha B are stable stars, like our Sun, and like our Sun may have been born surrounded by dusty, planet-forming disks.
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In 2008 scientists suggested that planets may have formed around one or both of these stars. From a telescope in Chile they are now monitoring Alpha Centauri very carefully to see whether small wobbles in starlight will show us planets in orbit in our nearest star system. Astronomers are looking at Alpha Centauri B to see whether this bright, calm star will reveal Earth-like worlds around it.
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Alpha A and Alpha B are binary stars. This means that if you were standing on a planet orbiting one of them, at certain times you would see two suns in the sky!
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Alpha Centauri can be seen from Earth's southern hemisphere, where it is one of the stars of the Centaurus constellation. Its proper name, Rigel Kentaurus, means “centaur's foot
.”
Alpha Centauri is its Bayer designation (a system of star-naming introduced by astronomer Johann Bayer in 1603).
“Me too,” said George. “Let's finish this. And find out who is sending those messages.”
“I'm calling the portal,” said Eric. On one side of the crater, they could already see the light of dawn as Alpha B hovered below the horizon. “Emmett!” he called. “Any chance of a trip back to Earth?”
“Not just yet,” said Emmett. “But I do have some reasonably good newsâ¦.”
“You've found us a planet that might be just right, a planet about the size of Earth in the Goldilocks Zone?”
“Affirmative,” said Emmett rather weakly. “Or at least, we've found something. It's our best guess. It's a moon, not a planet, though.”
“How is Cosmos holding up?” asked Eric.
“I just want you to know,” Mabel chipped in, “that I promised George's parents I wouldn't let him get into any trouble during his vacation! I'm going to have a very difficult time explaining this to Terence and Daisyâ¦.”
“Cosmos is functioning,” said Emmett nervously. “I've nearly finished updating the reverse portal. I'll be able to bring you in as soon as I've finished. Can you wait and I'll get you back to Earth?”
Bright rays of light were stealing across the crater, chasing the dark shadows away.
“No, we can't stay here any longer,” said Eric. “Send us onward, Emmett. And don't worry, Mabel. We'll be back.”
THE USER'S GUIDE TO THE UNIVERSE
THE GOLDILOCKS ZONE
Our Milky Way Galaxy contains at least one hundred billion rocky planets. Our Sun has four: namely, Mercury, Venus, Earth, and Marsâbut only Earth has life.
What makes Earth special?
The answer is
water
, especially in its liquid form. Water is the great mixer for chemicalsâbreaking them apart, spreading them out, and bringing them back together as new biological building blocks, such as proteins and DNA. Without water, life seems unlikely.
To support life, a planet's temperature must be between 32 and 212 degrees Fahrenheit (0 and 100 degrees Celsius) to keep the water in liquid form.
A planet orbiting too close to its home star will receive so much light energy that it will heat up to scorching temperatures, boiling all the water into steam.
Planets too far from their star will receive very little light energy, keeping the planet so cold that any water will remain as ice. Indeed, Mars has its water trapped as ice at the north and south poles.
There is a certain distance from every star where a planet receives as much
light
as it emits
heat
. That energy balance serves as a thermostat, keeping the temperature lukewarmâjust right to keep the water liquid in lakes and oceans. In this “Goldilocks Zone” around a star, any planets would stay warm and bathed in water for millions of years, allowing the chemistry of life to flourish.
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Geoff