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
Abbot, Charles Greeley
adenodes
adiantum myriosorum
administrator collection
alcyonaria (octocorallia)
atony of bladder sphincter
automatic cocking lever
Ban Mae Pang
Bandar-e'Abbās
beam penetration cathoderay tube
BICR
bipolar type ion-exchange membrane electrolyzer
bleed-type relay
brevin
Cabra de Mora
camrips
camshaft gear drive
certificate of deposit market
chemical diabetes
class libraries
controllable saturated shunt reactor
conversationists
croissard
cyberbullies
defining variable
dentinosteoid
examine the account
factfinder
family Polemoniaceae
fieldshifts
focal shutter
free of income-tax
friendshipy
gender intensification
golf stocking
groot karasberge (great karaz berg)
gum disease
hagenian
headachier
hecto-metre
hedge type assets
Hess, Walter
high resolution photoresist
I.X., IX
ice dump table
independent living
inward-focused
is this love
Laportea macrostachya
lasting manure
late-replicating x chromosome
livery
locked record
long-tailed pair
long-wave directional antenna
message unit call
mozart fifths
mykland
necrotizing arteritis
nerd pole
Olf-1
one-kick
outline feed
parasaccharomyces ashfordi
patch-clamps
polyethylene imine
prepreferential debt
prolixious
pumilio
pushaw
radiotriiodothyronine
raywid
reddled
roll sb over
sacral vein
scavenging-valve
scrap and hot metal practice
section of bosh
shout for help
silica-brick checkers regenerator
silver-leafed
simplicios
sneezy
sphenoethmoidal(suture)
ST_technology_telephone-equipment
stagewear
suffragate
summer fishing moratorium
sunflower cake
tank normal vapor vent
tetradecenic acid
thatchur
theandric
transaction processing system
transmitter optical connector
trend of staircase
unsickled
vapor blast process
variable field storage
writing requisition
X unit
zoological sciences