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
Airlander
alpha-rubber
Amarakaeri
anaphoria
animal protection test
automatic pirn changing mechanism
bad-debt
bailbond
bar type cylindergauge
beachlikest
Beta-Chlorovinyl
bind down
blowsies
BO, b.o.
bomerang
bos'n
cat's-eye retroreflector
Cesstibtantite
chargeing current
cheeselicious
computer program configuration item test procedure
contingency cost
countertrades
Cuatro Ojos
damage control table
DCUTL
different strokes for different folks
distribution clause
drag sb away
drift along
epidemic benign dry pleurisy
erythrophagocytosis
farmers' family
fitting of stuffing
flamin'
foam station
fornovo
frustum form factor
ganoderpurine
gas-glant planet
genus pholiss
Glycurone
gyroscopic seismometer
handson
have good sport
headborrow
hexaphenylethane
hiccuped
illegibly
image dissector, image-dissector
individual nominal characteristic
industrial gas
insulating refractories
intermolecular linkage
ivis
kibales
lead screw drive
lift van
luminance for scotopic vision
main supporting surface
Manoeuvring and Warning Signals
mismedications
Montsauche
mushrooms and fish maw in soup
new employee
non-destructivenonelectrolyte
non-toxic alcohols
nonglucocorticoids
nonnegativity conditions
ORCAELIDAE
orientation ratio
Ostycut
over-large
passenger person-kilometres
pcme
Peter Martyr d'Anghiera
piliary complex carcinoma
preaspirations
prob-lem
prop shaft
Prunella grandiflora
pully-bone
puncta optimum
quadruple-bogeys
raggi
rhizophlyctis variabilis
ring beam
Risulfazene
Rogelim
saxifragaceous
scuffler
Shueki
sintered phosphate
subalgebra
Suntrana
tilleth
trett
uncyclin
underground silo
units of analysis
UNJBS
water blinks