VOA慢速英语听力：科学家首次观测到与黑洞有关的引力波 Scientists Observe Gravitational Waves Linked to Black Holes for the First Time

VOA慢速英语听力：科学家首次观测到与黑洞有关的引力波 Scientists Observe Gravitational Waves Linked to Black Holes for the First Time

Scientists say that, for the first time, they have observed gravitational waves caused by black holes and other huge space objects moving through the universe.
科学家们表示，首次观测到了由黑洞和其他巨大太空物体在宇宙中移动而产生的引力波。

A group of international scientists using radio telescopes in North America, Europe, China, India and Australia made the observation.
一群来自北美、欧洲、中国、印度和澳大利亚的国际科学家利用射电望远镜进行了这项观测。

The existence of gravitational waves was first predicted more than 100 years ago by physicist Albert Einstein as part of his General Theory of Relativity. Einstein’s theory proposed that gravity is caused by a curving of space and time.
引力波的存在在100多年前首次被物理学家阿尔伯特·爱因斯坦预言，作为他的广义相对论的一部分。爱因斯坦的理论提出，引力是由空间和时间的弯曲引起的。

Scientists believe that, as gravitational waves travel through space, they press against and stretch everything they pass through. But researchers have struggled for many years to find solid evidence of the waves. In the 1970s, researchers found indirect proof by studying the motion of two crashing stars. That work was honored as part of the 1993 Nobel Prize in physics.
科学家们认为，当引力波穿越空间时，它们会对它们经过的一切施加压力并拉伸。但研究人员多年来一直努力寻找引力波的确凿证据。在1970年代，研究人员通过研究两颗相撞的恒星的运动找到了间接证据。这项工作因此获得了1993年诺贝尔物理学奖的一部分。

Then, in 2016, astronomers announced they had detected the first direct evidence of gravitational waves. That evidence came from an American-based research project known as the Laser Interferometer Gravitational-Wave Observatory, or LIGO. The LIGO project used ground-based telescope instruments to detect a gravitational wave produced when two black holes crashed into each other about 1.3 billion light years from Earth.
然后，在2016年，天文学家宣布他们已经探测到了引力波的首个直接证据。这个证据来自一个被称为激光干涉引力波天文台（LIGO）的美国研究项目。LIGO项目使用地面望远镜仪器探测了两个黑洞相撞产生的引力波，距离地球约13亿光年。

But the LIGO effort was only able to pick up waves at high frequencies. In the latest research, scientists were attempting to find low-frequency waves as a way to confirm gravitational wave signals.
但LIGO项目只能捕捉到高频率的引力波。在最新的研究中，科学家们试图寻找低频率的引力波来确认引力波信号。

The researchers said they successfully discovered such signals using about 15 years of data from a project called NANOGrav. This project has long used telescopes across North America to search for low-frequency gravitational waves. The results were recently published in a study in The Astrophysical Journal of Letters.
研究人员表示，他们成功地利用名为NANOGrav的项目约15年的数据发现了这样的信号。该项目长期以来一直使用分布在北美的望远镜搜索低频引力波。这些结果最近发表在《天体物理学通信》杂志上的一项研究中。

The research involved scientists aiming a series of radio telescopes at dead stars called pulsars. The pulsars send out radio wave signals as they spin around in space. These signals are so predictable that scientists know exactly when the radio waves are supposed to arrive on Earth. The pulsars are like “a perfectly regular clock ticking away far out in space,” said NANOGrav member Sarah Vigeland. She is an astrophysicist at the University of Wisconsin-Milwaukee.
这项研究涉及科学家们将一系列射电望远镜对准被称为脉冲星的死亡恒星。脉冲星在太空中旋转时会发出射电波信号。这些信号是如此可预测，以至于科学家们确切地知道射电波应该何时到达地球。NANOGrav成员萨拉·维格兰德说，脉冲星就像“太空中远离的一架完全规律的时钟”。她是威斯康星大学密尔沃基分校的天体物理学家。

But gravitational waves can affect the distance between Earth and the pulsars, which can change the signal activity. The researchers examined small changes in the ticking rate across 68 different pulsars. Some signals came early while others came late. The scientists said this research method provided enough evidence that gravitational waves were passing through.
但引力波可能会影响地球和脉冲星之间的距离，从而改变信号活动。研究人员检查了68颗不同脉冲星的滴答速率的微小变化。有些信号提前出现，而有些信号出现较晚。科学家们表示，这种研究方法提供了足够的证据证明引力波正在通过。

So far, this method has not been able to identify exactly where these low-frequency waves are coming from, said Marc Kamionkowski. He is an astrophysicist at Johns Hopkins University who was not involved with the latest research.
到目前为止，这种方法还无法准确确定低频引力波来自何处，马克·卡米昂科夫斯基说。他是约翰·霍普金斯大学的天体物理学家，没有参与最新的研究。

But Kamionkowski told The Associated Press the process does demonstrate how low-frequency gravitational waves appear to produce a continuous background “noise.” He compared the sound to what a person hears when standing in the middle of a party. “You’ll hear all of these people talking, but you won’t hear anything in particular,” Kamionkowski said.
但卡米昂科夫斯基告诉美联社，这个过程确实显示了低频引力波似乎会产生连续的背景“噪音”。他将声音类比于一个人站在派对中央时听到的声音。“你会听到所有人都在说话，但你不会听到具体的内容。”卡米昂科夫斯基说道。

The discovered background noise is “louder” than some scientists had expected, said Chiara Mingarelli. She is a member of the NANOGrav team and an astrophysicist at Yale University. Mingarelli told the AP this could mean there are more, or bigger, incidences of black holes coming together in space than previously thought.
发现的背景噪音比一些科学家预期的“更大声”，奇亚拉·明加雷利说。她是NANOGrav团队的成员，也是耶鲁大学的天体物理学家。明加雷利告诉美联社说，这可能意味着在空间中黑洞相互融合的情况比之前预计的更多或更大。

Or it may suggest there could be other sources of gravitational waves that could raise new questions about the formation of the universe. For example, another theory is that gravitational waves could be left over from a fast expansion period that came right after the Big Bang. The Big Bang is the explosion many scientists believe created the universe.
或者这可能意味着引力波可能来自其他源头，这可能引发关于宇宙形成的新问题。例如，另一种理论是引力波可能是在大爆炸之后的快速膨胀时期留下的。大爆炸是许多科学家认为创造了宇宙的爆炸事件。

Michael Keith was a member of the research team and works with the European Pulsar Timing Array, a collection of research telescopes. He said the galaxies between Earth and the Big Bang were likely "drowning out" such gravitational waves.
迈克尔·基思是研究团队的成员，并在欧洲脉冲星计时阵列（European Pulsar Timing Array）工作，这是一组研究望远镜。他说，地球和大爆炸之间的星系很可能“淹没”了这样的引力波。

In the future, scientists say low-frequency gravitational waves could provide even more information about early expansion of the universe. In addition, such a study could also help expand research on the mysteries of dark matter.
未来，科学家们表示，低频引力波可能会提供更多关于宇宙早期膨胀的信息。此外，这样的研究还有助于扩大对暗物质之谜的研究。

I’m Bryan Lynn.
我是布莱恩·林恩。

Words in This Story

curve – v. to form a curve: a line that bends continuously and has no straight parts

detect – v. to find or discover

frequency – n. the number of times a wave is produced within a particular period

tick – n. the sound a clock or watch makes each second when keeping time

source – n. where something comes from