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 big deal
adenomatous enteritis
Alnico alloyed nickel cobalt steel
amoibite (gersdorffite)
amphitrichous
anoopsia
ascending poliomyelitis
automatic autocollimator
Avitrol
basigene
be for the birds
bit yield
cable beach
cellulose acetate membrane electrophoresis
ceramic materials/devices
chain-type furnace
circumventable
coil pusher
commers
corrigendums
CPU time
cristae intertrochanterica
decontamination tank
dozes off
dread to think
dunninger
dynamic sequential control
elecltroreceptors
electrolysis vessel
elgodipine
enamel heat exchanger
equipotential cathode
general navigation computer
genomic exclusion
gli-
go to any length
group software
guessing at
haftara
Heptacarpus
horizontal experimental hole
iliotibial ligament of maissiat
islands of Calleja
khajuraho
kroeger
leucocladus
Lissapol L(or NX)
loth-to-depart
malfunctions
Mangole, Selat
marvelry
mesoionic compound
movable cage
multistage pricing
multisystem automatic test equipment
mutex
Nagagami R.
naveta
neuropuncture
nonpayer
nonplatonic
ormesher
packaged plant
pay-or-die
petroleum freezing point tester
pointclass
portability theory
power ballad
prismatic binoculars
pwy
pyogenicgranuloma
rat-ass
regular endorsement
renal tuberculosis with contralateral hydronephrosis
reproductive motivation
retroelement
rotary dump coupler
Rubus grayanus
Shizukuishi
shore-going
Shucushuyacu
sociophysicists
something like
south-south
stone hand
subambient chromatography
succinyl CoA synthetase
syimmetric(al)
to choke
to make fast to the mooring buoy
tranisent program table
tridiagonalization
truncated diagram
unnoisy
unsatisfies
varus deformity of heel
vehicula
velvet carpet
very open-grained pig iron
waste water treatment unit
webumentary
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