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
3-Hydroxycoumarin
aliunde
alternative motor fuels
anglo-celtic
approximationcurve
azidinblue
barrel churn
briefnesses
bulliform scale
Buseoksa
buttress dam
by pass governor
cerebral crisis
chirugion
cineromycin
debye interpolation formula
derye
dog's tooth violet
easdaq
equilibrium spectrum
equitable redemption
eugenics (galton 1883)
exchange visit
extrameningeal
fitch bitch
fluid friction brake
fuel pit support structure
furcellaran
goskomstat
Gualaguala, Pta.
hand deck-pump
hansen's
haploinsufficiency
helicoverpa
hierarchical diffusion of information
historiographership
howse
hydromagnocalcite (hydrodolomite)
hylomania
improperly posed
in-gathering
interferential filter
ironworks
Isetskoye
Karasburg
like a knife through butter
makerere
mandibular alveolar nerve (or inferior alveolar nerve)
Martino
maximum elastic strain energy
mission operation working group (mowg)
narrow upright tree
nemocardium exasperatum
nitrogen trichlorides
ommoral nature
original site
outcrack
palinuruss
Palwal
parkinsonias
part for ever
pigeon catch
pisspants
Pollaczek-Spitzer identity
potato desprouter
private banking
prostat-
quasimomentum
rear-view
redomiciles
reinforcement arrangement
restoration project
retorter
rollinson
rural route
Sargent County
Savanna la Mar
screened coal
Segmentum mediale
self sustain
selfism
sewage evaporator plant
sheep fever
shitta
shock excitation
spinal deformity
staser
statistical counter time lag
steel swarf
subcollege
submicrograms
sulphur dioxide probe
Surdila Greci
sweta
Tetracosamethylundecasiloxane
Thoscan
Tougué
tuberculous inflammation
vegetative map
verivakiss
vidich
yujiro