首页
财务会计
医药卫生
金融经济
考公考编
外语考试
学历提升
职称考试
建筑工程
IT考试
其他
登录
职称考试
Black Holes Trigger Stars to Self-destruct Scientists have long understood...
Black Holes Trigger Stars to Self-destruct Scientists have long understood...
admin
2020-12-24
32
问题
Black Holes Trigger Stars to Self-destruct
Scientists have long understood that supermassive (超大质量的) 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 (巴黎天文台) in Meudon, France,carried out computer simulations of the final moments of such an unfortunate star’s life,as it veered (改变方向) towards a supermassive black hole.
When the star gets close enough,the uneven forces flatten it into a pancake (薄饼)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 一 it will be completely destroyedBrassart says. Although the
explosion obliterates (使消失)the star,it saves some of the star’s matter from being devoured (吞没) 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 今 tarts swirling (旋动)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, US. “It may make it possible to see the disruption of that star immediately if it gets hot enough,” he says.
What would take place if a star gets too close to a black hole?
选项
A The black hole would rip the star apart.
B The star would veer away from the black hole.
C The black hole would reduce its own size considerably.
D The flattening process would reduce the star's density.
答案
A
解析
转载请注明原文地址:https://ti.zuoweng.com/ti/zdsQKKKQ
相关试题推荐
共用题干 Scientistsworkingonaproblemdonotknowandsometimescan'teveng...
共用题干 Scientistsworkingonaproblemdonotknowandsometimescan'teveng...
共用题干 Scientistsworkingonaproblemdonotknowandsometimescan'teveng...
共用题干 Scientistsworkingonaproblemdonotknowandsometimescan'teveng...
Anewgenerationofscientistsbecamefascinatedbydinosaurs.A:intriguedB:infe
40Otherscientists’experimentsaresimilartoHo’sinAthesizeoftheexperi
ScientistsDevelopWaysofDetectingHeartAttack Germanresearchershaveco...
ScientistsDevelopWaysofDetectingHeartAttack Germanresearchershaveco...
ScientistsDevelopWaysofDetectingHeartAttack Germanresearchershaveco...
ScientistsDevelopWaysofDetectingHeartAttack Germanresearchershaveco...
随机试题
(87-88题共用备选答案) A.温脾汤 B.小承气汤 C.黄龙汤 D.
病人甲输液中发生反应,经对症处置,症状消失,当天夜里出现心悸、呼吸困难,晨5时死
毕业教育的基本方法?
票据权利人为将票据权利出质给他人而进行背书时,如果未记载“质押”、“设质”或者“
要式合同是指( )的合同。(2012年真题) A、法律上已经确定了一定的名称
男性,32岁。十二指肠溃疡病史1年,口服药物治疗,因12小时前呕吐鲜血来诊,血压
对人体有潜在危险,对其安全性与有效性必须严格控制 A.第一类B.第二类
穿刺血样液体,但不凝固的为A.神经纤维瘤B.囊性淋巴瘤C.神经鞘瘤D.海绵型血管瘤E.杨梅型血管瘤
高倍数泡沫系统喷泡沫试验要求,喷水试验完毕,将水放空后,以手动或自动控制的方式对防护区进行喷泡沫试验,喷射泡沫的时间不小于()S,实测泡沫混合液的混合比...
共用题干 某运输企业位于市区,系自开票纳税人,2011年10月发生如下业务;(1)为某企业运输一批原材料,取得货运收入20万元,装卸收入3万元,仓储保管...