时间:2019-01-23 作者:英语课 分类:探索与发现2014年


英语课

 Tim has developed a map to visualize 1 their location. And on that map, the most important are the Near-Earth asteroids 3, the ones closest to the planet. On the screen here is a map of the solar system. 


 
And I’ve got the Sun in the centre and the third planet out here would be that of the Earth. The red dots in here are actually Near-Earth asteroids. The green ones are the regular Main-Belt asteroids. 
 
There are over 9,000 Near-Earth asteroids. But there’s one type that’re particularly concerned to locate, those asteroids that are over one kilometer in diameter. An Earth impact with one of these would spell disaster. Tim’s data reveals that there are 900 asteroids bigger than a kilometer in those dangerous Near-Earth orbits. But he has some good news.
 
Right now, there’s no information that any of those large objects will hit the Earth in the next 100 years. So we’re safe from impact of those objects for at least 100 years. So there are no catastrophic asteroid 2 impacts on the horizon. But there are still dangers out there. 

vt.使看得见,使具体化,想象,设想
  • I remember meeting the man before but I can't visualize him.我记得以前见过那个人,但他的样子我想不起来了。
  • She couldn't visualize flying through space.她无法想像在太空中飞行的景象。
n.小行星;海盘车(动物)
  • Astronomers have yet to witness an asteroid impact with another planet.天文学家还没有目击过小行星撞击其它行星。
  • It's very unlikely that an asteroid will crash into Earth but the danger exists.小行星撞地球的可能性很小,但这样的危险还是存在的。
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。
学英语单词
-acusis
aerial tuning indicator
analcite trachyte
ancient-soul
articel
ascending pyelonephritis
Aslavital
at the clearance sale
block square
bonsall
Būr Safājah
Cannon's test
cascade to
centrifugal pressure casting
cephalomotor
cloud dispersal
coal char
cost of maintaining a household
current voltmeter
cytr
damaged by worm
decayed tie
delay lens
Delevan National Wildlife Refuge
descriptive programming
digital library
dry(-seal) gasholder
efficiency of heat engine
equiprimordiality
extreme-skiing
final statement of accounts
foolishnesses
force motion
Fossa supratonsillaris
from the bottom of ones heart
GASB
genealoger
genus Choeronycteris
good-neighbor
half-joking
hand brake shaft
hereford (cattle)
hippiers
id number
in a huddle
in bad faith
initializers
intermittent positive control (ipc)
Italian iron
jacking-machine
Joint Communications-Electronics Committee
leukocytogenic sera
Lovibond glass standard
lutfisks
Lëtzebuerg
Mahra Sultanate
Matyrskoye Vdkh.
mauthausen
maximum operating power level
motyka
Murraya Koen. ex L.
Nebupent
network load
oculometroscop
opening sentence
palagonitized
pay streak
perfect form
poking borax
prophylls
Proto-Greek
pseudomonotone
pulvis causticus
Punam-gundo
put ons
quilpe
Ravennate
roadwidth
royal lily
sedimentary dike
solenoidal index
Sterculia pexa
straining cloth
strata filamentosum
systematic inorganic chemistry of metallic elements
teg wool
testing sifter
thinner ratio
threne
Tillamook County
training course
trihydroxypropylpterisin
uncorrected absorbance
undermeasurements
underoil
undroppable
upper aerofoil
UV radiation
waste filling
workers'party
WSAT
xyloidin