时间:2019-02-24 作者:英语课 分类:英语听力文摘 English Digest


英语课
Vesta 灶神星
 
You can see the planet Jupiter on a clear night, but Jupiter is humongous. Mars and Mercury are smaller than that, and you can see them, too. Wait a minute, our moon is even smaller, and you can see that. Could anything smaller than the moon be visible without a telescope?
 
Actually, yes. Though it takes a lot of patience and excellent sky conditions, it is possible to see a tiny object called Vesta. Although it had a molten interior and volcanoes, Vesta isn’t a planet or a moon: it’s an asteroidAsteroids are straychunks of rocky or metallic 1 materials that orbit the sun but were never drawn 2 into any of the planets.
 
Vesta is quite far away. Like many asteroids, it has an orbit out between the orbits of Mars and Jupiter. Astronomers 3 first spotted 4 it when looking for a new planet they thought should exist between these two.
 
As I said, Vesta is quite small–about three hundred and twenty-five miles across. So if it’s small and far away, how come we can see it from here? Vesta’s surface has a coating of pyroxine and olivine, two minerals that are actually also spewed up by volcanoes here on earth. They give it a whitish exterior 5 that reflects well, making it just possible to see Vesta with your eyes, even when the only two larger asteroids, Ceres and Pallas, are completely invisible.
 

 
在晴朗的夜空下我们能够看到木星,那是因为木星够大;尽管火星和水星比木星要小,但我们依然能看到。等等,月球更要小一些,我们还是能看到。那么,在不使用望远镜的情况下,我们还能看到比月亮更小的天体吗?
 
事实上,答案是肯定的。只要我们足够有耐心,天公也作美,我们还有机会看到一个小天体——它就是被命名为灶神星的小天体。尽管它以溶化的金属为核心且地表遍布火山,灶神星却既不是行星也不是月球:它仅仅是一颗小行星。小行星是由岩石或是金属块构成的小天体,他们绕太阳运动但绝不会卷入其他行星的运行轨道中。
 
灶神星距地球的距离很远。像其它许多小行星一样,它在火星与木星之间有自己的运行轨道。天文学家们首次发现它时是在寻找介于这两大行星间的另一个行星。
 
正如我所说,灶神星是很小的——它的直径也就只有325英里而已。那问题就是,它又小,距离我们又远,我们怎么能从地球上靠肉眼就看到它呢?在灶神星的表面覆盖了厚厚的一层玄武岩和橄榄石,这两种矿物质都是由此处的火上喷发而出的。这两种矿物质使得灶神星的表面呈白色,且发光的效果相当好。如此一来,我们便仅凭肉眼就可以看到灶神星了。甚至在比它还大的另外两个小行星——谷神星和智神星都无法看到的情况下,我们还是能看到它。
 
 
Note: spew up  喷出



 



adj.金属的;金属制的;含金属的;产金属的;像金属的
  • A sharp metallic note coming from the outside frightened me.外面传来尖锐铿锵的声音吓了我一跳。
  • He picked up a metallic ring last night.昨夜他捡了一个金属戒指。
v.拖,拉,拔出;adj.憔悴的,紧张的
  • All the characters in the story are drawn from life.故事中的所有人物都取材于生活。
  • Her gaze was drawn irresistibly to the scene outside.她的目光禁不住被外面的风景所吸引。
n.天文学者,天文学家( astronomer的名词复数 )
  • Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
  • Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪,为什么只有土星有光环。 来自《简明英汉词典》
adj.有斑点的,斑纹的,弄污了的
  • The milkman selected the spotted cows,from among a herd of two hundred.牛奶商从一群200头牛中选出有斑点的牛。
  • Sam's shop stocks short spotted socks.山姆的商店屯积了有斑点的短袜。
adj.外部的,外在的;表面的
  • The seed has a hard exterior covering.这种子外壳很硬。
  • We are painting the exterior wall of the house.我们正在给房子的外墙涂漆。
学英语单词
a licking
a terre
ABCP
advance person
Aleutic
allelotrope
animal and insect wounds
anode plate
back-up credit facility
base-apex line
Batpaysagyr, Peski
be glad to do
bear a charmed life
bench-marks
Bennite
cadmium laurate
calculated heading
carabiniere
carrier strip
Ceratodontidae
certie
Chenopodium gracilispicum
cirrata
clear outward
concha bullosa
continuous suture
cork product
detracin
developes
dix-hallpike
Dzaamar
ejected matter
energy conversion
fakon
farmway
fidelman
field of view (fov)
frequency of error
giant
gravity control point
great palisade
Hague rules
handbras
Hansetown
has an effect up on
hemiparaplegia spinalis
icers
immunosuppressive therapy
in show
intermediate-intermediate link
Ipomoea pes-tigridis
Jacques Etienne Montgolfier
jones criteria
katahn
kushites
labia minora
laesione fidel
legal operation
light reflection
Malva moschata
maximum angular velocity
mercuric naphtholate
metabology
metal glaze component
metalworking lubricant
methane-disulfonic acid
mutuatitious
non-polar material
non-print impulse
nongermanium
one way
osteoinduction
paracirrhites forsteri
parakaliella depressa
primitive flow table
product of sphere
pulmonary trunk
rale redux
reinvades
removal by ligature
Riesenbeck
roof ventilator
ruttles
silver stars
simple deterministic language
soubiran
sound good
spray broom
spur gear lubricant
strontium isotope
survivors
tammite
tapetal cell
throwing over
Tor B.
troubled debt restructuring
trypanosomoses
vitus berings
waistless
wampums
weak clay
WTCT