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
advs
alfred alistair cookes
alternating current selection
amphisapropel
aneurysm of carotid artery
anterior articular process
astern manoeuvring valve
auto-capacity
automatic conversion
black guillemots
black streaking
brachystachya
calender gauge
carotid atherosclerosis
carry-on baggage
centre porosity
cevine
chesteyns
chinese rose flower?
Clark County
cognet
complaint and claim
concrete shaft lining
coronetted
damnedest
dished pellet
distribution warehouse
dynamic transfer function
EAQ
El Coquillo
Esarhaddon
Faraday bag
fibergastrointestinalscope
fit curve
French-heeled
genus Salpinctes
glovesman
Google Zeitgeist
gravity seed cleaner
Greene, Nathanael
grid technique
handling problem
hare's fur
hauteur
hierarchy of subnet
historical resurrection model
host node
hotfixes
hypoimmunoglobulinemia
in your tracks
interia type starter
interlockings
know no boundaries
kumalo
kyano
late-career
laundry and hot shower effluents
liable jointly and severally
Ligularia alpigena
made shift
marine power resource
maximum convexity migration
Minnesota State University
mixed up
nail pulling
offer subject to goods being unsold
oil bowl
ootus
Oreticyl
osteosclerotic bone tuberculosis
Ottsjön
outside sill
pasado
patoulidous
pecuniary condition
pendent light
poolishes
purple apricots
reconvert
Retusotriletes
safety provision
scabrotrophon chunfui
show one's band
slit-lamp microscope
spacing parameter
splay brick
sterilisation
sulcus for subclavian artery
sumpture
swiveling propeller
tambourine
the operative word
thermal cracking gas chromatography
thickly settled
transient saliency
traveled distance
Triodanis perfoliata
vertebral artery type of cervical spondylosis
visual fire control
visual identification of pipe line
weighing rain-gage
Your trumpeter's dead!