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
aethylis aminobenzoas
aliassing
alongshore drift
anisamido
antimuon neutrino
aseismic slip
assisstants
bale band
barrier system
Betti group
calculus of common bile duct
cicognaras
coastal storm
composite family
Cooper's herniotome
covering roller
crimetime
defaults on
dialog box
dissatisfactoriness
dumpable tank
dunravens
energy degradation
estimation of required personnel
Euphorbia prostrata
Euphorbieae
flare nuclei
flat passage
flavopereirine
fracture mechanics model
galder
gas ammonia
generalized t2 distribution
glicks
graphitizing medium
grooved roller breaker
guide vane opening
hawkwoods
herzberg continuum
hitch crossbar
hourlong
hypomeralia
impulse wind tunnel
incliningly
Integrating ADC
invasion theory
jealoushood
Kachinic
kangaroo stoppie
kelp gull
khurd
lattice substitution
linoleum deck
lithium-magnesium reduction
longitudinal boom
lose yourself
Magu
marovitzs
match die process
mersause
Murzūq, Sha'bīyah
myiasis
nasal voice
nn. palatini
no ifs or buts
non-interactive
non-sked
nonimportation
novel theory
percussion power press
pi attenuator
polymeric ampholyte
possibility function
power station geothermal
Pyrrodoxyeycline
railroad logging
railway pier
receivability
remote data input
rust preventer
saddle ... with
shanoski
shell mould closer
simple signal
single sideband circuit
Slavnoye
solid state photodiode
sondern
stewed beef
sweet bellss
Tahli
tatonnement
the merest
tilletia horrida
transportation noise
un-famous
vertical spindle disc crusher
viral infections
wave function
wind shear indicator
worsted rubbing frame
Zangipur