New Data Adds to Understanding of 'Black Holes'
时间：2019-01-14 作者：英语课 分类：VOA标准英语2016年(九月)
New Data Adds to Understanding of 'Black Holes'
WASHINGTON —
Scientists continue to learn more about black holes in space, places where the pull of gravity is so strong that not even light can escape. Black holes occur after supergiant stars explode into brilliant but short-lived supernovas. All the matter dispersed 1 by that titanic 2 explosion collapses 3 in a few weeks or months, and gravity crushes it all into a tiny space. Now, data from a Japanese satellite is helping 4 decipher the secrets of these invisible singularities.
Black holes are invisible to the human eye. But telescopes with special tools can help find them by revealing how they affect nearby stars.
In February, Japan’s space agency rocketed its Astro-H satellite into orbit to examine large-scale structures in the cosmos 5, like supermassive black holes that exist at the center of most galaxies 6.
Unfortunately, after only about a month in space, the satellite fell apart. But before it went out of commission, it was able to gather vital data about the Perseus cluster, consisting of hundreds of galaxies 240 million light years from earth.
On board Astro-H was a unique X-ray spectrometer, which showed that superheated gas at the cluster's heart flows much more calmly than expected.
"And that gives us a very precise measurement of how much energy is being pumped into this gas by supermassive black holes, and so it allows us to form a more complete picture of how galaxies evolve, how the stars and the gas that will eventually cool out like rain to form the stars, evolves over cosmic time,” explained Brian McNamara, an astrophysicist at the University of Waterloo in Canada.
Researchers are also closely looking at the hot plasma—a type of matter--and gases that surround the galaxies.
"This is gas that has not cooled out and condensed out like rain in our atmosphere to form stars, planets, life, for example. So it's the potential for the future, and we're trying to understand what the future destiny of this galaxy 7 and many other galaxies would be,” said McNamara.
Supermassive black holes may manipulate how galaxies form and evolve.
“The energy released by these giant black holes is very tightly coupled to these atmospheres, which is the stuff out of which future stars will form,” said McNamara.
And this means the invisible giant at their heart influences the rate at which a galaxy grows.
- The clouds dispersed themselves. 云散了。
- After school the children dispersed to their homes. 放学后，孩子们四散回家了。
- We have been making titanic effort to achieve our purpose.我们一直在作极大的努力，以达到我们的目的。
- The island was created by titanic powers and they are still at work today.台湾岛是由一个至今仍然在运作的巨大力量塑造出来的。
- This bridge table collapses. 这张桥牌桌子能折叠。
- Once Russia collapses, the last chance to stop Hitler will be gone. 一旦俄国垮台，抑止希特勒的最后机会就没有了。
- The poor children regularly pony up for a second helping of my hamburger. 那些可怜的孩子们总是要求我把我的汉堡包再给他们一份。
- By doing this, they may at times be helping to restore competition. 这样一来, 他在某些时候,有助于竞争的加强。
- Our world is but a small part of the cosmos.我们的世界仅仅是宇宙的一小部分而已。
- Is there any other intelligent life elsewhere in the cosmos?在宇宙的其他星球上还存在别的有智慧的生物吗？
- Quasars are the highly energetic cores of distant galaxies. 类星体是遥远星系的极为活跃的核心体。
- We still don't know how many galaxies there are in the universe. 我们还不知道宇宙中有多少个星系。