在线英语听力室

Scientists Find Two ‘Wild’ Stars in Extremely Fast Orbit

时间:2022-11-04 01:57:14

搜索关注在线英语听力室公众号:tingroom,领取免费英语资料大礼包。

(单词翻译)

Scientists Find Two ‘Wild’ Stars in Extremely Fast Orbit

Unlike the sun, about half of the stars in our Milky1 Way galaxy2 orbit another star in what is known as a binary3 system. The word "binary" means two.

Researchers recently described an unusual binary system in the science publication Nature. The two stars orbit each other every 51 minutes in one of the fastest orbital periods known for a rare kind of binary system.

The two stars are about 3,000 light years from Earth. One light year is the distance light travels in a year.

The system belongs to a kind of binary star known as cataclysmic variable. That term describes a star system that can brighten by as much as 10,000 times for short periods.

The unusual system includes a star similar to our sun orbiting very closely to what is called a white dwarf4. A white dwarf is the hot and dense5 center of a burned out star.

Over billions of years, the distance between the two stars has decreased so much that they are now closer than the moon is to Earth.

Massachusetts Institute of Technology space scientist Kevin Burdge was lead writer of the study. He said, "Imagine if the moon zipped across the sky 10 times a night. That's the kind of speed we are talking about."

Because of the small distance between them, the white dwarf is taking material from the larger star.

The larger star is about the same temperature as the sun but it is now only the size of Jupiter, the largest planet in our solar system. The white dwarf has a mass equal to 56 percent of our own sun. It is extremely dense, however, because it is only 1.5 times the Earth's width.

Burdge said, "...when stars die of old age they become white dwarfs6 - but then this remnant began to eat its companion."

Burdge added that the white dwarf interrupted the normal development of the first star. He said the stars have been orbiting each other for 8 billion years.

The researchers used data from the Palomar Observatory7 in California and from telescopes in Hawaii and in the Canary Islands.

Stars are mostly made up of hydrogen, with smaller amounts of helium and other elements. In this system, the larger of the two stars has an unusually large amount of helium. Scientists say it lost hydrogen from its outer layers to the smaller white dwarf. At the same time, its hot center continues to make helium from existing hydrogen through the process of nuclear fusion8.

The binary system periodically brightens by a huge amount partly because the larger star is being pulled out of its normal shape by the white dwarf's gravity.

There are more than a thousand known cataclysmic variables. Only 12 or so have orbital periods below 75 minutes. While the binary system's 51 minutes is quick, it is not the record when compared to other kinds of binaries9.

The fastest known orbital period among binary stars is just five minutes and 21 seconds.

"There is tons of wild stuff going on in space," noted10 Burdge.

Words in This Story

galaxy --– n. any one of the very large groups of stars that make up the universe

burned out –v. (phrasal) to be burned or used up

zip – v. to move or act very quickly

remnant – n. the part of something that is left when the other parts are gone

companion –n. one of at least two stars orbiting in a binary or multiple star system

interrupt – v. to cause (something) to not be even or continuous

layer – n. an amount of something that is spread over an area


分享到:


点击收听单词发音收听单词发音  

1 milky JD0xg     
adj.牛奶的,多奶的;乳白色的
参考例句:
  • Alexander always has milky coffee at lunchtime.亚历山大总是在午餐时喝掺奶的咖啡。
  • I like a hot milky drink at bedtime.我喜欢睡前喝杯热奶饮料。
2 galaxy OhoxB     
n.星系;银河系;一群(杰出或著名的人物)
参考例句:
  • The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
  • The company has a galaxy of talent.该公司拥有一批优秀的人才。
3 binary jybzWZ     
adj.二,双;二进制的;n.双(体);联星
参考例句:
  • Computers operate using binary numbers.计算机运行运用二进位制。
  • Let us try converting the number itself to binary.我们试一试,把这个数本身变成二进制数。
4 dwarf EkjzH     
n.矮子,侏儒,矮小的动植物;vt.使…矮小
参考例句:
  • The dwarf's long arms were not proportional to his height.那侏儒的长臂与他的身高不成比例。
  • The dwarf shrugged his shoulders and shook his head. 矮子耸耸肩膀,摇摇头。
5 dense aONzX     
a.密集的,稠密的,浓密的;密度大的
参考例句:
  • The general ambushed his troops in the dense woods. 将军把部队埋伏在浓密的树林里。
  • The path was completely covered by the dense foliage. 小路被树叶厚厚地盖了一层。
6 dwarfs a9ddd2c1a88a74fc7bd6a9a0d16c2817     
n.侏儒,矮子(dwarf的复数形式)vt.(使)显得矮小(dwarf的第三人称单数形式)
参考例句:
  • Shakespeare dwarfs other dramatists. 莎士比亚使其他剧作家相形见绌。 来自《简明英汉词典》
  • The new building dwarfs all the other buildings in the town. 新大楼使城里所有其他建筑物都显得矮小了。 来自辞典例句
7 observatory hRgzP     
n.天文台,气象台,瞭望台,观测台
参考例句:
  • Guy's house was close to the observatory.盖伊的房子离天文台很近。
  • Officials from Greenwich Observatory have the clock checked twice a day.格林威治天文台的职员们每天对大钟检查两次。
8 fusion HfDz5     
n.溶化;熔解;熔化状态,熔和;熔接
参考例句:
  • Brass is formed by the fusion of copper and zinc. 黄铜是通过铜和锌的熔合而成的。
  • This alloy is formed by the fusion of two types of metal.这种合金是用两种金属熔合而成的。
9 binaries a620ad017ea8bd9bcc6be44fe1110dc1     
n.一双( binary的名词复数 );双体;二进制数;双子星
参考例句:
  • First MAME4ALL alpha binaries is out for testing purposes. 首个MAME4ALLα预览测试版是为了测试的目而放出的。 来自互联网
  • Security updates to the client binaries. 对客户端的二进制文件进行安全更新。 来自互联网
10 noted 5n4zXc     
adj.著名的,知名的
参考例句:
  • The local hotel is noted for its good table.当地的那家酒店以餐食精美而著称。
  • Jim is noted for arriving late for work.吉姆上班迟到出了名。

本文本内容来源于互联网抓取和网友提交,仅供参考,部分栏目没有内容,如果您有更合适的内容,欢迎 点击提交 分享给大家。