Mystery of star explosion 2000 years ago solved

 　　BEIJING, Oct. 26 (Xinhuanet) -- The question, why the first documented supernova was super-sized and grew so fast, has puzzled astronomers² for centuries. Now it is solved by US researchers.

　　The supernova, an exploded star, was observed in 185 A.D. and documented as a mysterious "guest star" by Chinese astronomers. It was visible for eight months.

　　Scientists later found the supernova, 8,000 light years away, was a bigger-than-expected supernova remnant. BBC reported that if the infrared³ light it emits could be seen by human eyes, it would appear to be as large as the full Moon in the sky.

　　Through observations in space telescopes, researchers of a latest study revealed that the explosion took place in a cavity in space, which allowed the star's remains⁴ to travel out much faster and farther. The study was published online in the Astrophysical Journal Monday.

　　The supernova was "two to three times bigger than we would expect for a supernova that was witnessed exploding nearly 2,000 years ago. Now, we've been able to finally pinpoint⁵ the cause," stated Brian Williams, lead author of the study and an astronomer¹ at North Carolina State University in Raleigh.

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 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。

4 remains   

n.剩余物，残留物；遗体，遗迹

参考例句：

• He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
• The remains of the meal were fed to the dog.残羹剩饭喂狗了。

5 pinpoint   

vt.准确地确定；用针标出…的精确位置

参考例句：

• It is difficult to pinpoint when water problems of the modern age began.很难准确地指出，现代用水的问题是什么时候出现的。
• I could pinpoint his precise location on a map.我能在地图上指明他的准确位置。