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
A5D5W
agathology
Amboinese, Ambonese
amplitude versus frequency characteristic
AOI AND-OR-invert
attributive use
auxiliary circuit socket for shed supply
back injury
baltes
Beatrix, (Beatrix Wilhelmina Armgard)
bitumina
board drop hammer
carbon-12
channel point
chuen
coal-tar industry
cocoswood
cold fog
corrosivenesses
cryptocephalus swinhoei
cumulative firing mechanism
cushion plant
dialyzates
diousand
dola
electrolytic action
electromagnetic pulley
explosion index
floating point computer
foetometry
ghorbanifars
gnatho-stomion
GRAMMATIDAE
greeve
hard sauces
indophenol
initial appropriation
intra-cutaneous
inukshuks
iremonger
iterative method of estimation
keep one's head
kicking stops
kimo
kondos
laser measurement application
latent pollutant
lilium duchartrei franch.
lipophage granulomatosis
liquia air
logistic control center (lcc)
magnertic hysteresis
Mazus saltuarius
Megginson
mononitrotoluene
Montigny-lès-Metz
non-floating arithmetic sign
non-linear load line
noun of assemblage
oversexed
ownerless movables
par value capital stock
perpetual bloom
phentetiothalein sodium
physiologic anemia
plumbago pot
Port engine half astern!
power transmission shaft
prelaughter
prosocial television
pulse.
puppy fat
pyrolytic conversion of hydrocarbons
rampant caries
RE (real number)
roccus saxatiliss
rotor axis
round-trip echo
Sappey's ligaments
scape-wheel
sedative bath
self-cleaning oil
shrivalties
silver diamminonitrate
singularis
Songjǒnman
splay-mouthed
stimulus-response correlation
stove bottom
Strategic Defense Initiative
strombs
supermarket key-entry system
suppression pool nozzles
Syrianism
text entry
thunder-head
timber seal
timeconstant
trade character
upflow principle
Vaassen
water filtration tank