时间:2019-01-23 作者:英语课 分类:探索与发现2013年


英语课

 But if you look carefully, stars aren't spread smoothly 1 across the whole sky. They are gathered together into a band that loops around the sky which we call the Milky 2 Way. 


 
That bright strip across the sky with its extraordinary abundance of stars and clusters was a clue to the nature of our galaxy 3
 
It was obvious to astronomers 5 for quite a long time that most of the stars were gathered together into a flats, layer or disk and that we were within that disk. But we still don't know whereabouts in the galaxy we are. And then in the early 20th century an American astronomer 4, Harlow Shapley, hits on a way of trying to find out where the centre of the galaxy might be. He used objects called globular clusters, which are actually found all over the sky. 
 
Bright sources containing thousands of stars, globular clusters are spread out in the sphere around the Milky Way's central disk. Shapley realized they were in effect signposts to where the centre of the galaxy could be found. 
 
He plotted where the clusters were and he found although they were spread all over the sky, they were concentrated in a particular direction. And that told us that we weren't at the centre of the galaxy, but the centre of the galaxy was in this direction here. So at last, astronomers knew exactly where the centre of the galaxy was and they also knew pretty much how far away it was.

adv.平滑地,顺利地,流利地,流畅地
  • The workmen are very cooperative,so the work goes on smoothly.工人们十分合作,所以工作进展顺利。
  • Just change one or two words and the sentence will read smoothly.这句话只要动一两个字就顺了。
adj.牛奶的,多奶的;乳白色的
  • 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。
n.星系;银河系;一群(杰出或著名的人物)
  • 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。
n.天文学家
  • 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。
n.天文学者,天文学家( astronomer的名词复数 )
  • 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》
学英语单词
a loaf of
abdominal nerve plexuss
active grate area
aminonitriles
anilinium oxalate
ball elbow
bare-foot
be right behind
bibliothecar
biological repair
C-spines
cassidyite
cc's
cerebral oximetry
contact procedure
contemporianism
cr.c
CRT
cryogenic circuit
current resolver
cyananthrol
dead hours of the night
decurions
defer to someone
direct analogy computer
Ductulus lacrimalis
effect of increased concentration
effective radium content
Ferrohortonolite
ferry vessel
Flieringa ring
fraudsman
furnace tilting mechanism
glitchier
gorlices
greasy spoon
Guard Glacier
hierarchical image understanding model
horizontal dry-back shell boiler
internet survey
interstitial atrophy
interwinding
Isodiane
jack lever
job development
Kentstown
Kyyjärvi
laborem
leather-jacket
Lenni Lenape
liberte,egalite,fraternite
liecester sheep
liquid column pressure ga(u)ge
loveseat
material metabolism
Morrisby mechanical ability test
multi-layer structures
Nairnsandstone
nitronaphthalin
non-euploid
nonavalanching photodiode
nonmatches
pakawops formosanus
papal bulls
paperhanging
parenthoods
parsley worm
path name block
Personal Genome Project
photovoltaic sub-array
pinakothek
pleiohomeotic
pre-historic
prescriver
primary zone
real estate market
regulator(gene)
resting metabolism
rhythmic mode
rotor side
sad-sack
safety recording instrument
Sangwǒn-gun
sector disk
sesamums
shortess
skip list
slag metal separation
smeu
Smoky River
strategic orbital weapon system
tail-rod guide
taxonomic approach
tfh
the world of
tonys
trauner
triglycine sulfate
Trotwood
ungreedily
verrucosum
worm one's way in