科学家们观察到有史以来最遥远的宇宙爆炸

Scientists Observe Most Distant Cosmic

Explosion Ever Recorded

科学家们观察到有史以来最遥远的宇宙爆炸

 

Astronomers² have detected the most distant explosion ever witnessed in the heavens. It was a flash so powerful that they could observe the faint light as it came in from almost the edge of the known universe. The discovery of this burst opens a new view into the frontiers of science.

 

The U.S. space agency's Swift satellite was routinely scouring³ the cosmos⁴ for exploding stars on September 4 when it spotted⁵ what scientists have since realized is the most distant such burst on record.

 

In astronomy, distance means time. The further something is away, the longer its light has been traveling to get to us. So the star blast is also the most ancient ever observed.

 

The space agency's chief investigator⁶ for the Swift spacecraft is Neil Gehrels.

 

Neil Gehrels: It was really exciting news for the Swift team when this Swift data were sent to the ground. This is exactly what we had built Swift to detect.

 

The exploding star the Swift satellite observed was typical of the death of a massive star. These blasts are the most powerful in the universe, sending out 100 million times the energy the Sun does in one year. They are not rare, but occur daily, emitting their light in high energy gamma rays. If you could see gamma rays, the sky would twinkle with such bursts.

 

As soon as Swift detected the explosion, ground telescopes worldwide were trained on the x-ray and visible light afterglow and confirmed the event.

 

University of North Carolina astronomer¹ Daniel Reichart measured the non-visible, infrared⁷ wavelengths⁹ of light from the dying star. His calculations show that the explosion occurred almost 13 billion years ago, close to the time of the cataclysmic explosion believed to have created the universe, the Big Bang.

 

Daniel Reichart: This cosmic explosion occurred 900 million years after the Big Bang. That may sound like a long time, but the universe is 13.7 billion years old, which means that this star exploded when the universe was six to seven percent of its current age.

 

The observance sets a new record for the distance and age of an observed star explosion. The next oldest exploding star ever witnessed took place 500 million years later.

 

However, the blast is important not for the superlatives that can describe it, but for what it can tell astronomers about the cosmos.

 

Donald Lamb: This is what we've all been waiting and hoping for.

 

This is University of Chicago astronomer Donald Lamb, who says the discovery provides a new tool to study the infant universe.

 

Donald Lamb: These bursts mark the moment of the first formation of stars, are tracers of the star formation history of the universe. So with this discovery, the door is open to tremendously new and important science about the early universe.

 

The finding comes less than a decade after scientists first learned that the gamma rays the exploding stars emit were coming from beyond our galaxy¹⁰. In fact, it was only three years ago that astronomers determined¹¹ what causes them. The Swift spacecraft was launched last November to cast a full time eye on them.

 

Donald Lamb predicts that astronomers will now begin finding even older, more distant star explosions to see even closer to the time the universe first lit up, thought to be about 600 million years after the Big Bang.

 

David McAlary, VOA news.

 

注释：

twinkle [5twiNkl] v. 闪烁，闪耀，（使）闪光

afterglow [5B:ftE^lEu] n. 晚霞，夕照

infrared [5infrE5red] adj. 红外线的

wavelength⁸ [5weivleNW] n. [物]波长

cataclysmic [9kAtE5klizmik] adj. 大变动的

the Big Bang 宇宙大爆炸

1 astronomer   

n.天文学家

参考例句：

• A new star attracted the notice of the astronomer.新发现的一颗星引起了那位天文学家的注意。
• He is reputed to have been a good astronomer.他以一个优秀的天文学者闻名于世。

2 astronomers   

n.天文学者，天文学家( astronomer的名词复数 )

参考例句：

• Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
• Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪，为什么只有土星有光环。 来自《简明英汉词典》

3 scouring   

擦[洗]净，冲刷，洗涤

参考例句：

• The police are scouring the countryside for the escaped prisoners. 警察正在搜索整个乡村以捉拿逃犯。
• This is called the scouring train in wool processing. 这被称为羊毛加工中的洗涤系列。

4 cosmos   

n.宇宙；秩序，和谐

参考例句：

• 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？

5 spotted   

adj.有斑点的，斑纹的，弄污了的

参考例句：

• The milkman selected the spotted cows,from among a herd of two hundred.牛奶商从一群200头牛中选出有斑点的牛。
• Sam's shop stocks short spotted socks.山姆的商店屯积了有斑点的短袜。

6 investigator   

n.研究者，调查者，审查者

参考例句：

• He was a special investigator for the FBI.他是联邦调查局的特别调查员。
• The investigator was able to deduce the crime and find the criminal.调查者能够推出犯罪过程并锁定罪犯。

7 infrared   

adj./n.红外线(的)

参考例句：

• Infrared is widely used in industry and medical science.红外线广泛应用于工业和医学科学。
• Infrared radiation has wavelengths longer than those of visible light.红外辐射的波长比可见光的波长长。

8 wavelength   

n.波长

参考例句：

• The authorities were unable to jam this wavelength.当局无法干扰这一波长。
• Radio One has broadcast on this wavelength for years.广播1台已经用这个波长广播多年了。

9 wavelengths   

n.波长( wavelength的名词复数 )；具有相同的/不同的思路；合拍；不合拍

参考例句：

• I find him difficult to talk to—we're on completely different wavelengths. 我没法和他谈话，因为我们俩完全不对路。 来自《简明英汉词典》
• Sunlight consists of different wavelengths of radiation. 阳光由几种不同波长的射线组成。 来自辞典例句

10 galaxy   

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。

11 determined   

adj.坚定的；有决心的

参考例句：

• I have determined on going to Tibet after graduation.我已决定毕业后去西藏。
• He determined to view the rooms behind the office.他决定查看一下办公室后面的房间。