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 BC
autopiloted
available input signal power
backreacts
basket
bezu
BSP test
cathedratical
consumer-generated
crocodylus acutus
cycle-criterion
Céüse, Montagne de
damp marsh
deadbeat
delivery man
Delsolin
dierickx
Distilben
dose meter
dynagraph
escaps
estate upon condition
Facts and Illustrations of Plants
filmnik
fine pith cutter
finite superposition
first-order condition
forward method
galbatorix
garbage out
Gargazzone
gate detector
guttae physostigminae
hathenes
heavy current
helium ionization detector
herdmate average
humidifying radiator
hydrogen cross section
Ilex godajam
imidophosphonic acid
inhir
initial shear thrust
inlive
judicial guarantee
Koz'modem'yanskoye
line of merchandise
make your voice heard
mameter
marrest
masolin
memory load
Miacalcic
micronome
miracle drug
mothers superior
mountain tai
multistratum control
niteroi (nictheroy)
numbering
Oletta
pan and roll tile
phenolics
pipe coiling machine
pipe-pushing
plain-paper
pneumatic filling
Poncyl
primitive logical formulas
printer margin
Prunus serrula
Qarah Būlāq
quarter sessions
radar direction finding
reategui
regular
Ryckmans
seismic qualification
sensationalizers
sexagenary
slice of matrix
specific Gibbs function
ST_building-and-engineering_road-junctions
stabilized animal fat
standard tooling
suspension systems
Swertia rosularis
tapping hammer
tariff concession
tetracosactide
the staggers
toggle lever arm
track controller
tractella
traitourly
transient part
trapped air-fuel ratio
treasure-hunt
tripod implant
wildlife parks
Zabaykalsky Krai
zero juncture