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
Acantharia
accelerated life
adoptive tolerance
apartment for the single
artificial filtering material
attempered
attributives
backshore terrace
basinal
bearhugged
bimembral
black-hat
Bloom-Torre-Machacek syndrome
building of refinery units
Caistor St Edmunds
callistethus formosanus
carcino-
channel-point detection
chiral amplification
chorologies
classical theory of value
concorporations
coverage probablity
cynthiana
damelin
du bois formula
duplication check
exchange classes
expansion scab scale
first-place finish
frement
fresh foods
gas tight housing
gas-generator
genus Lesquerella
girdle pain
heat-resistant explosive
herstory
high-frequency electrolysis
hybrid reserve
hyper-trophic osteoarthropathy
hyperama
incipit
incommensurablility
inlet pressure
integrated incident light
knocked-down in carloads
La Force
limiting magnitude
lipolytic enzyme
lomeli
long - term effect
long distance low loss transmission
lower rank
lunumidella
marginal oilfield
medium cleaning
medium size enterprise
memory-bound
most probable molecular velocity
negative forms
Nibelung
nong
noyls
ocular with outside focus
oil chemistry
overslop
perfect reflection
Philadelphus schrenkii
psuedo
Pyrus koehnei
radar technology
reduction table
residual oxygen
resolution enhancement
rostellums
rural infrastructure
rury
s-i-n
septicaemia pestis
shutter proof glass
single base powder
slim
split jet injector
spring inside caliper
steel bar straightening machine
strobotrons
sucker pole
surface of centers of principal curvature
take the gauge of someone
tape glass
topdressing
transmission light
trilinear interpolation
Trisetum bifidum
TSG
tupping
USAFSOC
utility poles
vertebra prominens reflex
vibrating plate furnace
wave field