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
adaptive metallurgy
adaptivenesses
age class method
applied mathematical modelling
argillaceous material
artful pleadings
back edge
bambusa pachinensis hay.
Bessel-Fourier transform
bolwer hat
boule weir
cascade type (washer)
central branches
chana dahl
charophyte
Closing Bell
crossflow rate
current
cutaway section
danger zone
darkling beetles
Deckenia
devolution
ditolylguanidine
double beam oscillograph
downy woodpecker
elementary electronic charge
ellroy
emulsion concentrates of petroleum products
enquiries
front-end system
fuel feed line
galactic diffuse light
genus limuluss
genus Seriphidium
GLONASS
gomphonema
good sailors
ground bearing capacity
guvnor
high precision face grinder
hipnotic
idleton
ilhan
interactive system control
intermediate box
inuncant
iontherapy apparatus
jet-flapped rudder
kkks
lay one's account for
lifting-body reentry
long-term planning
Main Pump
mhab
micropaedia
Mid-Atlantic Option
mientras
mill personnel
milli-ohm
MOVE statement
N-nitro-N-phenylbenzyl-amine
natural radiation
netmanage
norcamphane
nutmeg-shaped
observaciones
pantanencephalus
Patos de Minas
perimetritic abscess
personnel-related expenses
pidonia hohuanshana
placative
placket front
proprietarious
puccinia cyperi-iriae
red gums
remote-controller
return scrap
Rigid Sphere
sealing cone
shunt voltage regulator
single heading flight
solarex
SPHAERIOIDEA
substantive findings
subz
targeted value
teamkiller
textrons
third bottom
to ring a bell
Triphysaria chinensis
turbantop
United States Navy
velocity-compound turbine
veneer
Vilémov
waste weir
weapon maintenance team
white-on-black
zenithal projection