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
agricultural location theory
aikona
Akhunbabayev
Ardnarff
asham'd
automatic volume controller (avc)
balams
Barrack-Room Ballads
blonde lilians
buccal margin
butterof arsenic
carbon dioxide acidoses
catnapper
causgrove
cinearteriography
compression ignition engine
Cryptodiscus didymus
design aids
displaceabilities
double boils
ecological island
elementary fabric
emplectum
fixed material layout
float rudder
flood wave transformation
flow dichroism
gas distributor
gettings
Gunnedah
hfro
Hoa My
hub and spigot
in-plant test
indebted to
inductolog
isles of wight
Italian earth
james albert micheners
John Ruskin
kung sun ta niang
laughing goose
launch technique
Lithocarpus megalophyllus
living quality
magnetoacoustic
matzoon
miaowled
mibbes
microcredits
Mutual Fund Liquidity Ratio
neckedness
number six
offically
ophidine
ossipyte (ossipite)
overfining
ovulatio
paracondylar
parasitotropism
penecontemporaneous fold
permenorm alloy
Phacopida
pin-cushions
pipeweed
pocket instamatic camera
Polycotyledonae
power cut off switch
pro life
program source statement
rebound apparatus
redfords
repeated traffic
roast suckling pig
rope curve
rossouw
savi pouch
self-loading rifle
semiconductor fabrication imperfections
signal spillter
small calorie (cal)
sounding tube holder
southdeal
spark ionization source
spreader block
st. georges chan.
strengthenest
strobill
subcapsular hemorrhage of liver
Sulfacombinum
susceptor
sweet gas
the case
the great hungers
the sea-born city
thermostatically controlled bath
tidal stream arrows
tool maker
unregistered land
wall speedwell
wax-worker
willa cathers