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
GRE AWA 范文 ——Issue 4
GRE issue写作范文:研究经费
GRE考试写作范文——Issue 153
GRE考试写作范文——Issue 138
GRE写作话题:质疑精神(Skepticism)
GRE AWA 范文——Issue 13
GRE考试写作范文——Issue 152
GRE考试写作范文——Issue 150
GRE Issue写作提纲思路与分析29
GRE考试写作范文——Issue 142
GRE AWA 范文 ——Issue 1
GRE写作提纲思路与分析——issue 153
GRE写作提纲思路与分析——issue109
GRE考试写作范文——Issue 151
GRE AWA 范文 ——Issue 12
GRE考试写作范文——Issue 144
GRE高频作文分析与提纲:Issue144
GRE issue写作范文:复杂与简单
GRE issue写作范文:伟大含义的判定
GRE考试写作范文——Issue 146
GRE考试写作范文——Issue 157
GRE考试写作范文——Issue 147
GRE AWA 范文 ——Issue 5
新GRE写作Argument范文(十)
GRE issue写作范文:教学活动
GRE issue写作范文:钱是否花在当下
GRE考试写作范文——Issue 141
GRE issue写作范文:竞争利弊问题
GRE issue写作范文:现代技术
GRE AWA范文 ——Issue 3
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