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
acute depression
anal disc
as suways (suez)
assurance of conformity
babycenter.com
balance on liquidity
Barkos
Belyakov, Ostrov
binocular viewing system
boon
Boseonggang
bouvery
bowl centrifuge
bruit de choc
Buchwald's atrophy
burst type error
C. E. D.
calibration impulse
centage
Cephalanthera calcarata
chlorinated starch
coal quality log
colpomicroscopy
colpopexy
comedown
compact slag
compensation of damage
contron room
crioceris quatuordecimpunctata
diseased
dropping cut slice
educational process
elastic low par stock
electromagnetic fathometer
emulsifying power
endosclerotium
escape maneuver
fixed linkage mechanism
folding hatch cover
Ftalazol
gastrointestinal in-ner pressure transducer
hold hostage
inbourg
international practical temperature scale (ipts)
Iranian rial
irrigation in growing period
jaunting-car
joniak
Kapandriti
labial cartilage
lagrange intergration formula
latch position
laws and regulations of soil and water conservation
low-flow
market education
mastonia squalida
Mayan arches
multi-drum winch
multistrip laser
nansa
network of standing currencyswap arrangement
nicotinic acid hydrazide
non-taxable income
Olenekian
one-plies
onguent
passporting
Pedicularis dolichocymba
proemial
psychotically
put sb. through a catechism
quiet sun
rent-a-car
reverse payments
ride up to
rubble retaining wall
satellite signal
screw packer
sea sleeve
Serabend
ship's holiday
shortest common supersequence
shoshannah
stage-based piecework wage
structured display
sugarcane crusher
sulibaos
systema alimentariums
systematic names
table-clock
tank-top
thalpotic
Tigil'
transmission rod
trichopyton
unreclusive
ventri-mesal
virus hepatitis
vitamin X
wedge piece
whizzings
worked blue