Scientists have worked out when our Sun will die. It won’t be any time soon. It will be in 10 billion years. The scientists are from the University of Manchester in the UK. They predict that in about 5 billion years from now, the Sun will turn into a “red giant”. This is the scientific name given to a star at the end of its life. When our Sun becomes a red giant, its centre will shrink (收缩) . Its outer layers will expand (膨胀) as far as Mars. This means Earth will be burnt and disappear. After our Sun turns into a red giant, it will become a bubble of gas and space dust. The scientists say no humans will be on Earth when the Sun dies out.
The Sun is still quite young in space years. It is just 4.6 billion years old. This means it is only around one third into its lifespan (寿命) . Professor Albert Zijlstra, a scientist from the University of Manchester, explained what happens at the end of a star’s life. He said, “By this point in the star’s life, it is running out of fuel. Then it turns off and dies.” Professor Zijlstra was happy that modern science can count the age of stars and what will happen to them. “We even have found out what the Sun will do when it dies.” He said.
【小题1】According to the scientists, when will the sun die?【小题2】When do we call a star “red giant”?
【小题3】What will happen to humans when the sun dies out?
【小题4】What’s the lifespan of the Sun?
【小题5】Should we worry about the sun’s death? Why or why not?