时间:2019-01-23 作者:英语课 分类:探索与发现2014年


英语课

 Comparing the effects of an airburst with a ground strike, it seems the Chelyabinsk got away lightly. It’s estimated that the largest piece to hit the ground weighed 500 kilos, a fraction of the asteroid’s original mass of 7,000 tonnes. 


 
Now if a piece of rock that big had hit that area of Russia, it would have produced a huge impact crater 1. Then that kinetic 2 energy is then delivered into the ground and we see things like seismic 3 shock. So, you get … people would feel earthquakes on the ground.
 
So the fact that it was an airburst actually limited the consequences for the people on the ground. So, yes, still quite dramatic, still, you know, obviously, causing injuries. But it could have been a lot worse, had it survived down to ground.
 
Ground strikes are amongst the most destructive natural hazards we know of. When viewed from space, Earth’s encounters with giant asteroids 4 in its deep history are revealed. And there is evidence from our planet’s past of a truly devastating 5 meteorite 6 strike that decisively altered the course of life on Earth.   
 
Today millions of years after the impact, the evidence for that crater is well hidden. This is a gateway 7 to the cenotes, the unique cave system of Mexico’s Yucatan Peninsula.

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。
adj.运动的;动力学的
  • There exist many sources of energy both potential and kinetic.存在着许多势能和动能的能源。
  • The kinetic theory of gases is the best known example.气体动力学理论就是最有名的例子。
a.地震的,地震强度的
  • Earthquakes produce two types of seismic waves.地震产生两种地震波。
  • The latest seismic activity was also felt in northern Kenya.肯尼亚北部也感觉到了最近的地震活动。
n.小行星( asteroid的名词复数 );海盘车,海星
  • Asteroids,also known as "minor planets",are numerous in the outer space. 小行星,亦称为“小型行星”,在外太空中不计其数。
  • Most stars probably have their quota of planets, meteorids, comets, and asteroids. 多数恒星也许还拥有若干行星、流星、彗星和小行星。
adj.毁灭性的,令人震惊的,强有力的
  • It is the most devastating storm in 20 years.这是20年来破坏性最大的风暴。
  • Affairs do have a devastating effect on marriages.婚外情确实会对婚姻造成毁灭性的影响。
n.陨石;流星
  • The meteorite in Jilin Exhibition Hall is believed to be the largest in the world.吉林展览馆的陨石被认为是世界上最大的。
  • The famous Murchison meteorite smashed into the Australian ground in 1969.1969年著名的默奇森陨石轰然坠落在澳大利亚。
n.大门口,出入口,途径,方法
  • Hard work is the gateway to success.努力工作是通往成功之路。
  • A man collected tolls at the gateway.一个人在大门口收通行费。
学英语单词
.pot
abligated
aerocyanate
agglutinativeness
Aldinci
anchor barge
Anglo-Afghan Wars
ashd
bisannual
bivalent segmer
blue-sky thinking
bobber
boiler pan
bottle store
brain-cells
Bush, Vannevar
by name
califa
cart system
cenomanians
centre-spreads
choeradology
chromatoblast
close-to-critical range
coater
commacerate
component day
comptrollor
contact type strainmeter
controlcyliderrod
customs harbour
domestic partnerships
door closer
falderols
gage transformation
geography of railroad transport
glenlyon
glomsets
governor overriding control
guidance techinque
gumboro disease
Hansford County
henipavirus
Hollywood
humping zone
hypericum spathulatums
implementation tool
insulating mat
Irish goodbye
isohyomene
lepromin reaction
lung infection
magnetic dampling
maharaj
mask-focusing colour tube
Metanyl
minatory
minor break
mooleys
moricizine
multi-ram forging die
nickel chelate
nickel-plated double line iron screw hood
non-displacement condition
non-under control
normal year
Normet
ocean terminal
off one's chest
Old Negezi
phenolia
pleaching
Porzett splint
postnodular sulci
prematch
Profumo
push to talk switch
racing course
rent-a-cab
retoxification
risk fund
sax tubas
section-houses
senior executive
sleeping tablets
sleeps with
spilitic suite
spinner-type spreader
stomatorrhagia gingivarum
store-and-forward status save area
stub pen
styrene butadiene rubber
sub period
synoeoccus
tarboro
tenably
time adjusted investment
tractor guidance system
trigger-pull
Wimbleware
wool sorting
writs of prohibition