Black holes lead stars to self-destruct
Scientists have long understood that supermasvive black holes weighing. Millions or billions of suns can tear apart stars that come too close. The black holegravity pulls harder on the neatest part of the star, an imbalance that pulls the star apart over a period of minutes or hours, once it gets close enough.
When the star gets Close enough, the uneven forces flatten it into a pancake shape. Some previous studies had suggested this flattening would increase the density and temperature inside the star enough to trigger intense nuclear reactions that would tear it apart. But other studies had suggested that the picture would he complicated by shock waves generated during the flattening process and that not nuclear explosion should occur.
The devouring of stars by black holes may already have been observed, although at a much later stage. It is thought that several months after the event that rips the star apart, its matter starts swirling into the hole itself. It heats up as it does so, releasing ultraviolet light and X-rays.
Brassart aggress. Perhaps it can be observed in the X-rays and gamma rays, but its something that needs to be more studied,he says. Supernova researcher Chris Fryer of the Los Alamos National Laboratory in Los Almos, New Mexico, US, says the deaths of these stars are difficult to simulate, and he is not sure whether the researchers have proven their case they exploded in the process.
A the black hole could tear apart the star
C the black hole could dwindle its size considerably
2. According to the third paragraph, researchers differed from each other in the problem of
B whether the stars would increase its density and temperature
D whether the uneven forces would flatten the stars
A No nuclear explosion would be triggered inside the star
C. Much of the stars matter thrown by the explosion would be beyond the black holes reach
4. What will happen several months after the explosion of the star?
B the black holes matter will heat up
D the black holes matter will release ultraviolet light and X-rays
雅思口试的通关之道及至上之策
雅思范文--父母是否应该花更多的时间同子女在一起
让范文走开 雅思作文范文不再风光
9.14福州雅思考试回忆
拿到雅思成绩后对雅思考试的回顾
听读说写的技巧和学习方法
我在悉尼考雅思
雅思心得--给为雅思而倍受折磨的朋友
深圳雅思考试内容详解
作文V101格式及观点一览
雅思考试会换题吗?
2月23日上海雅思A类考试经历
雅思考试心得(推荐)
我对雅思TASK2作文的几点体会
首次合格英文成绩 我在悉尼考雅思
上海雅思G类考试全真记录
奥克兰8.24雅思回忆
一点实力+速走捷径=顺利考到6.5分
雅思考试的一点实战经验
雅思范文--是否应将动物关在动物园里
关于IELTS练习和训练材料选择的建议与看法
我是怎样准备IELTS的(英)
我的IELTS感受和一些零星技巧
IELTS考试喜获7.5分的详细攻略
我的雅思考前总结(9/14)
奥克兰8月10日的学术类雅思考试
月初满分备考经验
IELTS Oral test(7 20)
雅思培训不尽人意 如何选择好学校
雅思范文--机器翻译与学外语的contradiction
不限 |
英语教案 |
英语课件 |
英语试题 |
不限 |
不限 |
上册 |
下册 |
不限 |