新托福黄金精选阅读【PDF高清下载】.docxVIP

智课网TOEFL备考资料新托福黄金精选阅读【PDF高清下载】 摘要： 新托福黄金精选阅读是2015年以来托福考试界最受欢迎的资料之一，究竟新托福黄金精选阅读的亮点在哪里，下面我们就来简单了解一下，同时有需要下载的小伙伴扫描页面中的二维码即可获得。 新 托福 黄金精选阅读里面的真题全部来源于ETS官网，且每一篇文章都附有详细的解析和答案，对我们备考 托福阅读 非常有用.....,可以说 新托福 黄金精选阅读几乎是人手一本的精华资料。 新托福黄金精选阅读： Europa is the smallest of planet Jupiter’s four largest moons and the second moon out from Jupiter. Until 1979, it was just another astronomy textbook statistic. Then came the close-up images obtained by the exploratory spacecraft Voyager 2, and within days, Europa was transformed-in our perception, at least-into one of the solar system’s most intriguing worlds. The biggest initial surprise was the almost total lack of detail, especially from far away. Even at close range, the only visible features are thin, kinked brown lines resembling cracks in an eggshell. And this analogy is not far off the mark. The surface of Europa is almost pure water ice, but a nearly complete absence of craters indicates that Europa’s surface ice resembles Earth’s Antarctic ice cap. The eggshell analogy may be quite accurate since the ice could be as little as a few kilometers thick –a true shell around what is likely a subsurface liquid ocean that , in turn, encases a rocky core. The interior of Europa has been kept warm over the eons by tidal forces generated by the varying gravitational tugs of the other big moons as they wheel around Jupiter. The tides on Europa pull and relax in an endless cycle. The resulting internal heat keeps what would otherwise be ice melted almost to the surface. The cracklike marks on Europa’s icy face appear to be fractures where water or slush oozes from below. Soon after Voyager 2’s encounter with Jupiter in 1979, when the best images of Europa were obtained, researchers advanced the startling idea that Europa’s subsurface ocean might harbor life. Life processes could have begun when Jupiter was releasing a vast store of internal heat. Jupiter’s early heat was produced by the compression of the material forming th