时间:2019-01-26 作者:英语课 分类:自然百科2012年


英语课

 In the four decades since our robots first arrived, the once fuzzy ball at the end of our telescopes has steadily 1 focused into a red planet we can understand, and it is not a welcoming place. The problem is the atmosphere is so thin and cold that water exists only as solid ice in the ground or vapor 2 in the air, not as liquid on the surface. You might see some fine wispy 3 clouds, high in the sky, but don’t bother bringing an umbrella. 


 
The whole planet is dryer 4 than the dustiest desert on earth, and there hasn’t been a drop of rain here for millions, perhaps billions of years. The thing that fascinated me was that we could see valleys, sneaking 5 across the surface that had clearly been carved by flowing water, so this is telling us that in the past it was different, not only that it was different in a way that made more suitable for life than it is today, and that I found truly compelling. 
 
We are very convinced that one time it was very hospitable 6 planet, with liquid water and enough atmosphere to sustain the climate, and so now we are trying to understand how did it change, why did it change and what still might be on Mars. 
 
These are deep Martian mysteries. If Mars and earth started as sister planets, did life once festoon the Martian surface? Might it still be there? And where did all the atmosphere and water go? 
 
Solving these puzzles has challenged our planetary explorers from the moment the first Martian postcards were sent back to earth. It’s the fact that it is so much like earth that kind of makes Mars such a special place.

adv.稳定地;不变地;持续地
  • The scope of man's use of natural resources will steadily grow.人类利用自然资源的广度将日益扩大。
  • Our educational reform was steadily led onto the correct path.我们的教学改革慢慢上轨道了。
n.蒸汽,雾气
  • The cold wind condenses vapor into rain.冷风使水蒸气凝结成雨。
  • This new machine sometimes transpires a lot of hot vapor.这部机器有时排出大量的热气。
adj.模糊的;纤细的
  • Grey wispy hair straggled down to her shoulders.稀疏的灰白头发披散在她肩头。
  • The half moon is hidden behind some wispy clouds.半轮月亮躲在淡淡的云彩之后。
n.干衣机,干燥剂
  • He bought a dryer yesterday.他昨天买了一台干燥机。
  • There is a washer and a dryer in the basement.地下室里有洗衣机和烘干机。
a.秘密的,不公开的
  • She had always had a sneaking affection for him. 以前她一直暗暗倾心于他。
  • She ducked the interviewers by sneaking out the back door. 她从后门偷偷溜走,躲开采访者。
adj.好客的;宽容的;有利的,适宜的
  • The man is very hospitable.He keeps open house for his friends and fellow-workers.那人十分好客,无论是他的朋友还是同事,他都盛情接待。
  • The locals are hospitable and welcoming.当地人热情好客。
学英语单词
address the problem
amphirhopalum ypsilon
analcimization
asartone
aspirations
Berthe
bow loading and discharge arrangement
CABRA numbers
Canadian hemlocks
canonical ordering
cationic detergents
citizens committee
clearing away the heat located at Shaoyang Channel
closing-out sale
coastal dynamics
column-like
corporicity
credit boycott
cross air blasting
cund
cyser
Dalwallinu
Deerhorn Gelatin
dial flow meter
double riveting
dravya
dressed fish
duck stool
excited state spectroscopy
exterior wall finish
fair leather
family papaveraceaes
fasigyne
fast pin hinge
father
flash furnace
fold with fractures
fragmenting
game-cover
genus Ephippiorhynchus
gonorrheal exanthem
guestfriendships
hsrs
integrated mica
internal reflection element
laboulbenia egens
Las Herencias
Liverpool head
local distribution data interface
low pressure heat treatment
Ludwigsfeld
lysiteles digitatus
made yourselves master of
mean time between maintenance action
muddle-up
multiplex nevus
multivariable
navigation periscope
non-lubricated compressor
non-steroidal anti-inflammatory drug
obumbrates
odd-lot differential
oil globule
oratorship
overdriving
overhaul(ing) check
pachyprotasis erratica
partial aplasia of brain
penetration of the coulomb barrier
physiological moisture
program segment size
public-art
recursion tree
redoxidation chamber
revolution per second
rhyacophila madalensis
Robert Abram Bartlett
Roegneria breviglumis
ruttiers
sapolu
satellite inspection
scaled division
schistosum
scoffage
screen house
sefi
self-gravity
single tube
sloths
sonic reflection
standard and recommended practices (sarps)
stripping of the boundary layer
substantial in content
tcgas
tele-visions
tick-seed
unbalanced budget
unhumanly
variegated pyrite
waywitty
with a ill grace
working chamber of caisson