首页
外语
计算机
考研
公务员
职业资格
财经
工程
司法
医学
专升本
自考
实用职业技能
登录
外语
Black Holes Trigger Stars to Self-Destruct Scientists have long understood that super massive black holes weighing millions
Black Holes Trigger Stars to Self-Destruct Scientists have long understood that super massive black holes weighing millions
admin
2011-01-02
73
问题
Black Holes Trigger Stars to Self-Destruct
Scientists have long understood that super massive black holes weighing millions or billions of suns can tear apart stars that come too close. The black hole’s gravity pulls harder on the nearest part of the star, an imbalance that pulls ’the star apart over a period of minutes or hours, once it gets close enough.
Scientists say this uneven pulling is not the only hazard facing the star. The strain of these unbalanced forces can also trigger a nuclear explosion powerful enough to destroy the star from within. Matthieu Brassart and Jean-Pierre Luminet of the Observatoire de Paris in Meudon, Francel, carried out computer simulations of the final moments of such an unfortunate star’s life, as it veered towards a super massive black hole.
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 be complicated by shock waves generated during the flattening process and that no nuclear explosion should occur.
The new simulations investigated the effects of shock waves in detail, and found that even when their effects are included, the conditions favor a nuclear explosion. "There will be an explosion of the star—it will be completely destroyed," Brassart says. Although the explosion obliterates the star, it saves some of the star’s matter from being devoured by the black hole. The explosion is powerful enough to hurl much of the star’s matter out of the black hole’s reach, he says.
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.
If stars disrupted near black holes really do explode, then they could in principle allow these events to be detected at a much earlier stage, says Jules Halpern of Columbia University in New York, US2. "It may make it possible to see the disruption of that star immediately if it gets hot enough," he says.
Brassart agrees. "Perhaps it can be observed in the X-rays and gamma rays, but it’s something that needs to be more studied," he says. Supernova researcher Chris Fryer of the Los Alamos National Laboratory in Los Alamos, New Mexico, US3, says the deaths of these stars are difficult to simulate, and he is not sure whether the researchers have proven their case that they explode in the process.
Something destructive could happen to a star that gets too close to a black hole. Which of the following destructive statements is NOT mentioned in the passage?
选项
A、The black hole could tear apart the star.
B、The black bole could trigger a nuclear explosion in the star.
C、The black hole could dwindle its size considerably.
D、The black hole could devour the star.
答案
C
解析
短文的第一和第二段提供了答案。第一段第一句说,特大质量的黑洞能够撕裂靠近它们的恒星;第二段的第二句说,由于它们之间力量的悬殊,恒星内部会发生核爆炸。第五段提及黑洞吞噬恒星的问题。C的内容文章中没有找到,所以应该选择C。
转载请注明原文地址:https://kaotiyun.com/show/G8Ld777K
本试题收录于:
职称英语理工类A级题库职称英语分类
0
职称英语理工类A级
职称英语
相关试题推荐
NiagaraFallsisagreattouristsite,drawingmillionsofvisitorseveryyear.
ScientistsDevelopWaysofDetectingHeartAttackGermanresearchershavecomeupwithanewgenerationofdefibrillators(除颤
ScientistsDevelopWaysofDetectingHeartAttackGermanresearchershavecomeupwithanewgenerationofdefibrillators(除颤
ScientistsDevelopWaysofDetectingHeartAttackGermanresearchershavecomeupwithanewgenerationofdefibrillators(除颤
ScientistsDevelopWaysofDetectingHeartAttackGermanresearchershavecomeupwithanewgenerationofdefibrillators(除颤
ScientistsDevelopWaysofDetectingHeartAttackGermanresearchershavecomeupwithanewgenerationofdefibrillators(除颤
WhyDon’tBabiesTalkLikeAdults?Overthepasthalf-century,scientistshavesettledontworeasonabletheoriesrelatedto
随机试题
简述因素分析法的基本程序。
胡适给中国公学十八年级毕业生的赠言是______。
Doweneedlawsthatpreventusfromrunningriskswithourlives?Ifso,thenperhapslawsareneededprohibitingthesaleofc
A.升高B.明显减少C.明显增高D.常减少E.正常或减少胃癌胃酸表现为
甲与乙订立一份买卖乙之汽车的合同,约定总价款40万元。由甲分5期支付完成,在甲付清全部款项之前。乙保留对该汽车的所有权。汽车转移给甲并办理变更登记之后,乙又以该车向丙抵押借款30万元。对此,下列说法错误的有:()
建设程序,是指()在整个建设过程中,各项工作()的先后顺序。
在进行设备监理单位与业主之间的组织协调时,由于设备监理单位接受业主的委托,对设备工程项目进行监理,因此应首先维护业主的法定权益,应尽一切努力使工程按规定的时间期限、按规定的质量、在规定的预算内建成。总监理工程师及全体监理人员应()。
以演示账套“巨力公司”为基础资料。编制收款单据:1月12日,农业银行收到B公司商业汇票人民币80000元,支付前欠货款,请编制收款单并保存。
汇率的标价法
软件危机是软件产生过程中出现的一种现象,下述现象()是其主要表现。Ⅰ.软件需求增长难以满足Ⅱ.软件开发成本提高Ⅲ.开发进度难以控制Ⅳ.软件质量不易保证
最新回复
(
0
)