2015-04-10 BBC:星光七纪元-24

（单词翻译）

 This tiny companion to the bright Dog Star, was dubbed¹ the pup. And by 1922, this new type of the star had an official classification. It was called a white dwarf². But naming it was the least of scientists’ problems. When they compared its size to its mass, something extraordinary emerged. It was denser³ than anything on earth, denser than anything previously⁴ imagined. They were a type of star that shouldn’t exist. The burnt down remains⁵ if one of fusion⁶ has stopped. The fuel exhausted⁷, so how can they still shine? Mysteries, that have long intrigued⁸ professor John Aleis. Throughout their lives, stars make their energy by fusing together lighter⁹ nuclei¹⁰ to make heavier ones. They start off with hydrogen, then the helium, then they go on to fuse together helium to make carbon and oxygen. And as the time goes on they burn out more and more this fuel, until eventually, it’s like a car, even run out the gas. With its helium burning days at the end, the white dwarf active life is over. All it’s left with is a dead core of carbon and oxygen. It’s not really a star at all, but a cinder¹¹ and an internal battle raging in the heart of the star, between gravity and fusion, now has a clear victor.