'George,' said Cosmos in his mechanical voice, 'there are billions and billions of stars in the Universe. Unless you are as clever as me, you will not be able to count them all.'
'Cosmos, why are there so many?' asked George in wonder.
'New stars are created all the time,' answered the great computer. 'They are born in giant clouds of dust and gas. I am going to show you how it happens.'
'How long does it take for a star to be born?' George asked.
'Tens of millions of years,' replied Cosmos. 'I hope you are not in a hurry.'
'Tut-tut,' said Eric, sitting cross-legged on the floor beside the sofa, his long thin limbs bent at sharp angles. He looked like a friendly giant spider. 'Don't worry, George, I've speeded it up quite a lot. You'll still get home for dinner. Annie, pass the crisps around. I don't know about you, George, but the Universe always makes me very hungry.'
'Oh dear,' said Annie, sounding embarrassed. There was a rustling noise as she rootled around inside the big bag. 'I'd better get some more.' She leaped off the sofa and dashed back to the kitchen.
As Annie left the room, George noticed something about the view through the window onto outer space: not all of it was covered with little stars. In the bottom corner of the window he saw a patch of total darkness, a place where not a single star shone.
'What's happening there?' He pointed.
'Let's have a look, shall we?' said Eric. He pressed a button on a remote control and the view through the window seemed to zoom towards the dark patch. As they got closer, George realized that an enormous cloud was hovering in that spot. The window kept moving forward until they were right inside the cloud itself, and George could see it was made of gas and dust, just as Cosmos had said.
'What is it?' he asked. 'And where is it?'