Do the preparation task first. Then read the text and do the exercises.
Dr Tomas Streyer looked around the control room at his team of scientists and engineers. He was pretending to be calm, but he was both excited and terrified. The next few minutes would be the starting point of years more research towards understanding the secrets of how the universe began.
He looked out of the window at the beautiful blue summer sky and took a deep breath.
'Ready,' he said, and pressed the first button, bringing to life the complicated computers and machines around them.
'Set,' he said, and pressed the second button, switching on the huge particle accelerator that lay in a huge underground laboratory, deep beneath the towns and fields of Switzerland.
'Go,' he said, at exactly twelve o'clock, and pressed the final button.
For a second, everything went absolutely black, as if he had gone blind. Tomas cried out in shock, but the lights were already on again. Whatever that was, it was not supposed to have happened.
'Everybody check the systems!' he ordered, but nothing seemed to be wrong with them. The particle accelerator was working, just as he had hoped it would.
'Look outside,' said Tomas's assistant in a frightened voice.
Instead of the perfect summer day of five minutes ago, the sky was darker than the blackest night. Not only had the sun disappeared, there weren't even any stars.
People were shouting and screaming, calling their families on the telephone, afraid they had all suddenly disappeared too. Tomas ignored their noise. He sat at the main computer and started reading the data from his experiment. Nothing there explained what was happening. He rushed for the exit, his team running behind him until they were all outside the laboratory building.
Everyone else in the research centre was outside, panicking and confused. They were using the screens and torches on their mobile phones to see where they were going, waving them around like giant fireflies.
Several people got in their cars and turned on the headlights, driving them to the entrance to make a small area of brightness in the dark for everybody to crowd together. When the automatic street lights turned on, some people cheered, but most of them were still frightened.
Then, almost twenty minutes after Tomas had started his experiment, without warning the sun reappeared in the sky, warm and yellow, and the black sky turned blue again. Everyone started laughing and dancing around, and Tomas breathed a sigh of relief.
But later, hours later, when the real night fell again, no one was celebrating. Because although the moon rose as usual, there was not a star to be seen.
No one wanted to know what Tomas had intended to happen or what his research had actually been about. What did that matter? All they cared about was what had happened. He had stolen all the stars – or that's what the newspapers said he had done. And when they put him on trial before the International Criminal Court, that's what they charged him with: stealing the stars.
He pleaded 'Not guilty'.
'Well, if you didn't steal the stars, Dr Streyer,' said the lawyer for the prosecution, 'what did you do?'
'As far as my experiment is concerned,' said Tomas, 'it didn't seem to do anything. The machine was working, that's all.'
'Taking the stars from the sky seems like nothing to you?' The lawyer looked around at the audience in the court. 'No one here would agree. No one in the world.'
'That's not what I meant,' said Tomas. 'What I know is that when the experiment started, there were suddenly no photons in the test room.'
'What? Photons? We aren't all scientists here! Speak plain English, Dr Streyer!'
'Light,' said Tomas. 'I mean, for just a moment it was as if there was no light in our laboratory, and then we saw it was dark outside as well until the daylight returned to normal.'
'Normal, Dr Streyer? Except for when …' – the lawyer checked his notes – '... the sun went out for exactly 16 minutes and 40 seconds? Oh yes, the rest of the day was very normal. The night, on the other hand, hasn't been normal ever since.'
Tomas nodded sadly. 'I know. But you must believe me, nothing I did could possibly have removed the stars from existence!'
'So neither you nor your experiment stole the stars from us,' said the lawyer.
'No,' Tomas said.
'You just made it so that we can't see them any more.'
After a long pause, Tomas sighed. 'Yes.'
The lawyer raised an eyebrow. 'How is that any different?'
Tomas didn't have an answer, not one anyone would understand anyway, let alone believe. He had a theory, but it would take years to prove it.
Instead, he changed his plea to 'guilty'.
The trial gave the world someone to blame for what it had lost, but sending Tomas to prison for years wouldn't change anything. Instead, at the end of their symbolic trial, they gave him a symbolic punishment.
Tomas was sentenced to work at the abandoned Extremely Large Telescope in Paranal, Chile. Nobody looked at the night sky now. No tourists climbed high mountains to see the edges of our galaxy, and no scientists asked for money to study the empty sky. All that passed through the night sky was the lonely moon, a handful of planets and the occasional comet. Looking up made people depressed.
Tomas thought it was fair. It was right that he should be punished, and working as an astronomer had become almost the same as prison. After a few years the world forgot about him, or at least decided to leave him alone. Every evening he would watch the sun go down. It vanished below the horizon exactly eight minutes and twenty seconds after it actually descended below the curve of the Earth. The laws of physics remained the same, much to Tomas's daily relief. Light still travelled at the same speed as it always had. He hadn't changed reality that much or, at least, he hoped he hadn't. If light travels at a certain speed, he thought, perhaps absence of light travels at the same speed.
Of course, there was no way to prove his theory. Not yet. And, alone in the observatory, Tomas had nobody to share it with anyway.
High in the mountains of Chile, Tomas continued to watch the night, his enormous telescope pointing towards a particular point of the sky, even though it was always just as empty as every other part. And each day, as the sun went down, he thought of the song his parents sang to him as a child:
Star light, star bright,
First star I see tonight,
I wish I may, I wish I might,
Have the wish I wish tonight.
For 1,596 black nights – nearly four and a half years – there was no change to the night sky. But that was OK. It didn't disprove Tomas's theory, it supported it. Tomas thought about the absence of light he had created and he imagined it like a wave, passing the sun and continuing out towards the edge of our galaxy and beyond. It would take 1,596 nights to pass the nearest star, and another 1,596 nights for that star's light to reach the Earth again … If the wave of darkness existed at all, of course. If his calculations were correct. If he was wrong, the stars really were gone forever.
And then one night, another 1,596 nights later, almost nine years after the disaster, Tomas looked up from his telescope and saw Alpha Centauri twinkling back at him.
The first star.
He wiped the tears from his eyes and made a wish. Billions of other people's wishes followed right after it.
Story written by Andrew Leon Hudson and adapted by Nicola Prentis.