万物简史 第181期:爱因斯坦的宇宙(24)

 　　In 1919, now aged¹ thirty, he moved to California and took up a position at the Mount Wilson Observatory² near Los Angeles. Swiftly, and more than a little unexpectedly, he became the most outstanding astronomer³ of the twentieth century.

　　1919年，他已经30岁。他迁到加利福尼亚州，在洛杉矶附近的威尔逊山天文台找了个职位。非常出人意料的是，他很快成为20世纪最杰出的天文学家。

　　It is worth pausing for a moment to consider just how little was known of the cosmos⁴ at this time. Astronomers⁵ today believe there are perhaps 140 billion galaxies⁶ in the visible universe. That’s a huge number, much bigger than merely saying it would lead you to suppose. If galaxies were frozen peas, it would be enough to fill a large auditorium—the old Boston Garden, say, or the Royal Albert Hall. (An astrophysicist named Bruce Gregory has actually computed⁷ this.) In 1919, when Hubble first put his head to the eyepiece, the number of these galaxies that were known to us was exactly one: the Milky⁸ Way. Everything else was thought to be either part of the Milky Way itself or one of many distant, peripheral⁹ puffs¹⁰ of gas. Hubble quickly demonstrated how wrong that belief was.

　　让我们稍停片刻，先来考虑一下当时人们对宇宙的了解是如何少得可怜，这是值得的。今天的天文学家认为，在可见的宇宙里也许有1400亿个星系。这是个巨大的数字，比你听了这话认为的还要巨大得多。假如把一个星系比做一粒冻豆子，这些豆子就可以塞满一个大礼堂——比如，老波士顿花园或皇家艾伯特大厅。（有一位名叫布鲁斯·格雷戈里的天体物理学家还真的计算过。）1919年，当哈勃第一次把脑袋伸向望远镜的时候，我们已知的星系数只有一个：银河系。其他的一切要么被认为是银河系的组成部分，要么被认为是远方天际众多气体中的一团气体。哈勃很快证明这种看法是极其错误的。

　　爱因斯坦珍贵照片

　　Over the next decade, Hubble tackled two of the most fundamental questions of the universe: how old is it, and how big? To answer both it is necessary to know two things—how far away certain galaxies are and how fast they are flying away from us (what is known as their recessional velocity). The red shift gives the speed at which galaxies are retiring, but doesn’t tell us how far away they are to begin with. For that you need what are known as“standard candles”—stars whose brightness can be reliably calculated and used as benchmarks to measure the brightness (and hence relative distance) of other stars.

　　在之后的10年里，哈勃着手研究有关宇宙的两个最基本的问题：宇宙已经存在多久？宇宙的范围有多大？为了回答这两个问题，首先必须知道两件事——某类星系离我们有多远，它们在以多快的速度远离我们而去（即现在所谓的退行速度）。红移能使我们知道星系后退的速度，但不能使我们知道它们离得有多远。为此，你需要有所谓的“标准烛光”——即准确测得的某个恒星的亮度，作为测算其他恒星的亮度（并由此计算其相对距离）的基准。

1 aged   

adj.年老的，陈年的

参考例句：

• He had put on weight and aged a little.他胖了，也老点了。
• He is aged,but his memory is still good.他已年老，然而记忆力还好。

2 observatory   

n.天文台，气象台，瞭望台，观测台

参考例句：

• Guy's house was close to the observatory.盖伊的房子离天文台很近。
• Officials from Greenwich Observatory have the clock checked twice a day.格林威治天文台的职员们每天对大钟检查两次。

3 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。

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 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》

6 galaxies   

星系( galaxy的名词复数 )； 银河系； 一群（杰出或著名的人物）

参考例句：

• 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。

7 computed   

adj.[医]计算的，使用计算机的v.计算，估算( compute的过去式和过去分词 )

参考例句：

• He computed that the project would take seven years to complete. 他估计这项计划要花七年才能完成。 来自《简明英汉词典》
• Resolving kernels and standard errors can also be computed for each block. 还可以计算每个块体的分辨核和标准误差。 来自辞典例句

8 milky   

adj.牛奶的，多奶的；乳白色的

参考例句：

• Alexander always has milky coffee at lunchtime.亚历山大总是在午餐时喝掺奶的咖啡。
• I like a hot milky drink at bedtime.我喜欢睡前喝杯热奶饮料。

9 peripheral   

adj.周边的，外围的

参考例句：

• We dealt with the peripheral aspects of a cost reduction program.我们谈到了降低成本计划的一些外围问题。
• The hotel provides the clerk the service and the peripheral traveling consultation.旅舍提供票务服务和周边旅游咨询。

10 puffs   

n.吸( puff的名词复数 )；（烟斗或香烟的）一吸；一缕（烟、蒸汽等）；（呼吸或风的）呼v.使喷出( puff的第三人称单数 )；喷着汽（或烟）移动；吹嘘；吹捧

参考例句：

• We sat exchanging puffs from that wild pipe of his. 我们坐在那里，轮番抽着他那支野里野气的烟斗。 来自辞典例句
• Puffs of steam and smoke came from the engine. 一股股蒸汽和烟雾从那火车头里冒出来。 来自辞典例句