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
adaptation syndrome
advanced industrial country
aglaonemas
alipoidic
Arkhangel'skoye
arteriograrm
atomist theories
backing of rafters
black ink figure nation
bunkums
bus-rod
Carex orthostachys
cartagenas
cognovit judgment
cold-pressing
common sequence
commutation zone
cutesy-pie
Dianhydrodulcitolum
drive sb potty
eirene
equal validity
Eradex
Esk.
ex officio magistrate
externa bark
fascial sheath of prostate
fast color
front elevation drawing
furacana(e)
Garciaz
general Cayley algebra
go off the boil
hard cosmic ray
Hemandifoline
highwayman
hybrid signature
i remember
imperial preferential tariff system
in a flutter
indium oxide
initial operation
Institution of Electronics
intensifer
kapaa
Keenania tonkinensis
Lancang
lesser curvature(stomach)
light diaphoretic prescription
living environment
lysionotin
meitneriums
microinfusion
miniatus
Muhlenberg, Frederik Augustus Conrad
non-experiences
non-prosecution
nonstandard bearing
off-street parking
ognissanti
os1 carpale distale secundum
palmicolous
phoneticism
plain hook
Poa attenuata
position dialing
postmodern campaign
pre-defense
precalcination
press corrector
pseudotuberculosis aspergillaris
pulsed aerosol generator
quality of tobacco
recombiner
register wheels
reserve protein
retailed
reverse multiple
rochate
roman churches
rudiments of tank gunnery
Schesaplana
self-revealings
short-lived radioactive substance
shottage
single event effects
sintered ferrous product
sleepy sicknesses
smaller whole tone
sonar optimum frequency
specific storage
spiderwick
Spinacia oleracea L.
tenoch
the top of the market
undiversifiable risk
Unitarian Universalism
unscheduled downtime
volumetric correction factor
Vostochnaya Litsa
water locust
whitemarsh