VOA慢速英语2018 科研人员：银河系中心存在许多黑洞（在线收听）

Researchers: Many Black Holes in Center of Milky Way Galaxy

Astronomers say the center of our galaxy has plenty of strange, super gravity objects.

天文学家称在我们银河系的中心有大量陌生的超引力物体。 

For years, scientists believed that circling the center of galaxies, including our own Milky Way galaxy, were not only stars, but lots of stellar black holes.These are stars that have collapsed, creating gravity so strong even light does not get out.

许多年来，科学家认为围绕着星系（包括我们的银河系）中心的不仅有恒星，还有许多恒星黑洞。这些黑洞是已经崩塌的恒星产生强大的地心引力造成的，甚至连光都穿不透。

But scientists had yet to find evidence of black holes at the center of the Milky Way until now.

但是科学家至今都在寻找证据，以证明银河系中心存在黑洞。 

Astronomers studying old x-ray observations have found signs of at least 12 black holes in the inner circle of the Milky Way.And since most black holes cannot be found that way, they believe that there are likely thousands of them there.

研究旧X射线观测的天文学家已经在银河系的内圈发现了至少12个黑洞迹象。因为大多数黑洞都无法以这种方式被发现，因此他们认为那里很有可能有数千个这样的黑洞。

In fact, a study suggests there may be more than 10,000 black holes in the center of our galaxy.The findings appear in the journal Nature.

实际上，一项研究表明在我们银河的中心存在上万个黑洞。这项发现发布在《自然》杂志上。 

Chuck Hailey is an astrophysicist at Columbia University in New York.He was the lead writer of the report.He told the Associated Press, “There’s lots of action going on there. … The galactic center is a strange place.That’s why people like to study it.”

查克·海利是纽约市哥伦比亚大学的一名天体物理学家。他是这份报告的主要作者。他告诉美联社说：“那里进行着很多活动……银河系中心是一个陌生的区域，这就是人们喜欢研究它的原因。”

Scientists already know about a supermassive black hole at the center of the Milky Way.They call it Sagittarius A.

科学家已经在银河系的中心发现一个超大质量的黑洞。他们将其称之为人马座A。 

Supermassive black holes are the largest kind of black hole, being between a million and billion times bigger than others.This latest research shows that the newly discovered stellar black holes are in addition to Sagittarius A and they do, in fact, circle it.

超大质量黑洞是最大的一种黑洞，比其他种类的黑洞要大至少一百万倍甚至高达十亿倍。最近的研究表明，除了人马座A之外，还存在其他新发现的恒星级黑洞，实际上它们是围绕着人马座A的。

The newly discovered black holes are within about 31 trillion kilometers from the supermassive black hole at the center of the Milky Way.So there is still a lot of empty space and gas among all those black holes.But Hailey noted that if you looked at the amount of space around Earth, there would be zero black holes, not thousands.

新发现的黑洞大约在距银河系中心的超大质量黑洞31万亿千米内。所以仍然有很多真空区和气体存在于这些黑洞中间。但是海利说如果你看看地球周围的空间的话，那就会是零个黑洞而不是上千个。

Our planet is part of a spiral arm circling the Milky Way.It is about 9.5 trillion kilometers, or 3,000 light years, from its center.In the rest of our galaxy, scientists have only identified about 60 black holes to date, Hailey added.

我们的星球是围绕着银河系的旋臂的一部分，距银河中心约有9.5万亿千米或者说是3,000光年。海利补充道：在我们银河系的其他地方，科学家到目前为止只确定了大约60个黑洞。

Harvard astrophysicist Avi Loeb was not part of the latest study.He called the findings exciting, but noted that they confirmed what scientists had long expected.

哈佛大学的天体物理学家阿维·洛布并没有参与这项最新的研究。他称这项发现很令人兴奋，并指出这些发现证实了科学家们长期以来的预期。

The newly confirmed black holes are about 10 times the mass of our sun.In comparison, Sagittarius A has the mass of 4 million suns.

新确认的黑洞质量大约是太阳的十倍。相比之下，人马座A的质量是太阳的400万倍。 

The recently discovered black holes are also only the kind that are binary, meaning they are partnered with another star.Black holes partnered with other stars produce large amounts of x-rays as the black holes pull in the star’s outer layer.Those x-rays are what astronomers observe.

最近发现的黑洞也只是一种双星系黑洞，意为他们是和其他的恒星相伴随的。随着黑洞吸入恒星的外层，黑洞与其他恒星合力产生大量X射线，这些X射线就是天文学家观测的目标。

When astronomers look at closer binary black hole systems, they could then compare what is seen with what is too weak to be observed from far away.Using that information, Hailey believes that there must be 300 to 500 binary black hole systems.

当天文学家观察更近的双星黑洞系统时，他们可以将就近观察到的系统与因为远距离而太过微弱以至于无法观测的系统进行对比。通过这一信息，海利认为那里肯定存在着300个到500个双星黑洞系统。

Binary black hole systems are likely only five percent of all black holes, he added.So that means there are really thousands of them.

他补充说道：双星黑洞系统可能只是所有黑洞的5%。因此这意味着真的存在上千个黑洞。 

Hailey said there are good reasons the Milky Way’s black holes are usually in the center of the galaxy.First, their mass most often pulls them to the center.But mostly the middle of all those stars is the perfect place for black hole formation, with lots of dust and gas.

海利说这就很好地证明银河系黑洞通常存在在星系的中心。首先，他们的重量通常会将他们拉入中心。但是伴随着大量的尘埃和气体，大多数恒星的中间部分是黑洞形成的绝佳地点。

He said it is “sort of like a little farm where you have all the right conditions to produce and hold on to a large number of black holes.”

他说这“类似于一个小农场，在这里你有所有充足的条件来生产和保留大量的黑洞”。 

Words in This Story

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

stellar – adj. of or relating to the stars

x-ray – n. powerful invisible rays that can pass through various objects and that make it possible to see inside things, such as the human body

spiral – n. a circular curving line that goes around a central point while getting closer to or farther away from it

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