首页
登录
职称英语
Lunar sight-seeing trips and orbiting space hotels are within reach, moon wal
Lunar sight-seeing trips and orbiting space hotels are within reach, moon wal
游客
2023-12-21
75
管理
问题
Lunar sight-seeing trips and orbiting space hotels are within reach, moon walking astronaut Edwin"Buzz" Aldrin said last week, but some who favor space tourism worried about its "giggle factor". Astronomers have known for years that a source of intense energy emissions lies at the center of the Milky Way Galaxy, obscured from view by vast clouds of dust and gas. In February, 1992, researchers at the Max Planck Institute in Garching, Germany, reported evidence that the mysterious energy source is a gigantic black hole.
Observations have shown that many strong energy sources lie at the heart of the Milky Way. One of them, called Sagittarius A, is thought to be the actual center of the Galaxy, the point about which the great spiral of stars rotates. Sagittarius A is a powerful emitter of radio waves and X-rays.
Astronomers have considered two possible explanations for the identity of Sagittarius A. They theorized that it is either a compact duster of normal stars or a super-massive black hole containing as much as a million or more suns. The German scientists reported that they found strong evidence in support of the black hole explanation.
The astronomers used a new telescope high in the Andes Mountains of Chile to obtain the sharpest images ever made of the region around Sagittarius A. The image shows that Sagittarius A is a single, small object rather than a duster of stars.
The researchers also found that a bubble of gas is expanding outward from Sagittarius A. This expanding gas is similar in temperate, density, and composition to the jets of gas that astronomers have observed flow hag away from the centers of many other galaxies. Such jets are thought to be generated by accretion disks surrounding enormous black holes. Accretion disks are vast, swirling masses of gas and dust that give off titanic amounts of energy as they are sucked into the black hole. The similarity between the jets emitted by some galaxies and the gas bubble surrounding Sagittarius A supports the idea that Sagittarius A is a super-massive black hole. [br] According to the German researchers, the energy source at the center of the Milky Way Galaxy ______.
选项
A、has been covered up by vast clouds of dust and gas
B、still remains unknown to astronomers
C、has proved to be a black hole
D、actually provides power for the rotation of file great spiral of stars
答案
C
解析
文章第一段最后一句话提到“researchers at the Max Planck Institute in Garching,Germany,re ported evidence that the mysterious energy source is a gigantic black hole”,由此可知,他们已经证明了能量的来源是巨大的黑洞,因此[C]为正确答案。
转载请注明原文地址:https://tihaiku.com/zcyy/3291635.html
相关试题推荐
Lunarsight-seeingtripsandorbitingspacehotelsarewithinreach,moonwal
Lunarsight-seeingtripsandorbitingspacehotelsarewithinreach,moonwal
Lunarsight-seeingtripsandorbitingspacehotelsarewithinreach,moonwal
Lunarsight-seeingtripsandorbitingspacehotelsamwithinroach,moonwalk
TheFamilyThenandNow Thingswerenevereasywithinthefam
TheFamilyThenandNow Thingswerenevereasywithinthefam
TheFamilyThenandNow Thingswerenevereasywithinthefam
TheFamilyThenandNow Thingswerenevereasywithinthefam
TheFamilyThenandNow Thingswerenevereasywithinthefam
TheFamilyThenandNow Thingswerenevereasywithinthefam
随机试题
[img]ct_epem_epelisv_01811(20097)[/img][br][originaltext]Jackisaverygood
AftertheviolentearthquakethatshookLosAngelesin1994,earthquakesci
AftertheviolentearthquakethatshookLosAngelesin1994,earthquakescie
下列各项洋地黄毒性反应的处理措施,错误的是A.洋地黄特异性抗体治疗 B.频发室
下列作家与作品对应正确的是()。A.《白杨礼赞》——朱自清 B.《分马》——赵
近代以来,世界上主要资本一帝国主义国家,几乎都曾经欺凌过中国,强迫中国签订过不平
下列关于口服降糖药物的叙述都是正确的,除了A.有酮症倾向的1型糖尿病忌用磺脲类降
一住店客人未付房钱即想离开旅馆去车站。旅馆服务员揪住他不让走,并打报警电话。客人
下列关于地方政府规章的表述中,正确的是()。A.各级人民政府都有权制定地方政府
消毒效果检查方法及评价指标
最新回复
(
0
)