时间:2019-02-05 作者:英语课 分类:自然百科2012年


英语课

 And it’s here in a freezer that Messenger will encounter another puzzle: can ice exist on a planet so close to the sun?


 
It's only when the first radar 1 observations to the surface of Mercury were obtained back in the 90s that it was discovered that Mercury in fact, had what appeared to be polar caps in these first radar images.
 
Some corners of Mercury’s polar craters 3 are in permanent shadow. Here, on the most sun-baked planet of all, water seems to survive frozen in / eternal darkness.
 
The ice is contained in places where literally 4 the sun never shines, and so the ice is quested in these dark, interiors of craters of the high latitude 5 regions.
 
We found the same thing on our moon. In late 2009, the LCROSS mission crashed a probe into a deeply shadowed crater 2 confirming ice hidden near the lunar South Pole. Where did it come from? A comet? 
 
It's very interesting. Because we believe that the water in the earth, in its atmosphere, in the oceans, and even below the surface, probably came from the similar source, and so part of the mystery of Mercury is to try to find out where the water came from, and maybe that might help us find out where the water of earth came from. 
 
It may never be possible to send a human to Mercury, but how about a robot? In 2011, when Messenger arrives in orbit, imagine this tough little spacecraft circling a lonely planet a very long way from home.

n.雷达,无线电探测器
  • They are following the flight of an aircraft by radar.他们正在用雷达追踪一架飞机的飞行。
  • Enemy ships were detected on the radar.敌舰的影像已显现在雷达上。
n.火山口,弹坑
  • With a telescope you can see the huge crater of Ve-suvius.用望远镜你能看到巨大的维苏威火山口。
  • They came to the lip of a dead crater.他们来到了一个死火山口。
n.火山口( crater的名词复数 );弹坑等
  • Small meteorites have left impact craters all over the planet's surface. 这个行星的表面布满了小块陨石留下的撞击坑。 来自《简明英汉词典》
  • The battlefield was full of craters made by exploding shells. 战场上布满弹坑。 来自《现代英汉综合大词典》
adv.照字面意义,逐字地;确实
  • He translated the passage literally.他逐字逐句地翻译这段文字。
  • Sometimes she would not sit down till she was literally faint.有时候,她不走到真正要昏厥了,决不肯坐下来。
n.纬度,行动或言论的自由(范围),(pl.)地区
  • The latitude of the island is 20 degrees south.该岛的纬度是南纬20度。
  • The two cities are at approximately the same latitude.这两个城市差不多位于同一纬度上。
学英语单词
acid water pollution
actual catch
ad police
aerovironment
Anoectochilus zhejiangensis
atmospheric vacuum distillation process
batch purifier
bellhousing
bilocular, biloculate
bimetallic material
boot loaders
burning mixture
buttonmakers
call management
chibnall
Chlamydoselachindae
coated cutting tool
commutating flux
cut off current
cytorrhyctes aphtharum
discriminal
doagh isle
electrotransport process
engine speed
ESTJ
examinates
fascine dyke
Frobenius ring
Froude brake
full adder output
full pre-stressing
gapless rail
gibed
Glacier Bight
golden shares
Googlewhack
have an ear for sth
heterophilic
hydraulically equivalent particles
hydroxy-benzyl chloride
hypanisopanthism
intercrystalline brittleness
interstitial fluids
jutted
Keota
Lauterbourg
load-tipping moment
lymphogranulomas
Matulji
media manipulation
metal resistance thermometer
milk-churn
minor modes
miost sauff
monovalnet
monsoon rain
multiflavored
nano-circuits
Orchilla, Pta.
order-disorder trans formation
ordinary piece rate method
ov
overbought position
pan crusher
pilotage form
power system abnormality
Prayssas
Protocaliciineae
pulse generator
quartile range
rainbow nation
red podzolic laterite
reputations
reversible circulation
Rockefeller, John Davison
rural economy
saddle nose
sales voucher
scincid lizard
secondary cosmic radiation
selection core matrix
severiano
short irradiated
single-wire system
sistren
site exploration
slag tank
sonic navigation
source alphabet
stafffloat
statutory immunity
strengthenest
subscandens
successively
superficial folliculitis
surface induction
taxes and levies
thawing weather
Tryškiai
us buyer
weak tie
zincky