时间:2018-12-08 作者:英语课 分类:VOA标准英语2014年(五月)


英语课

 


Hubble's Dazzling Mission Nears Its End 哈勃太空望远镜使命渐入尾声


The Hubble Space Telescope has changed the way we see the universe.


For almost a quarter of a century, it has sent vast amounts of data and images from space. A new exhibit at the Smithsonian National Air and Space Museum in Washington documents how Hubble’s remarkable 1 success has hinged on its ability to be repaired and serviced in orbit. 


Hubble was launched aboard the Space Shuttle Discovery in 1990. Mission Control saw something it hadn’t expected: fuzzy images. Hubble Space Telescope Program Manager Douglas Broome delivered the troubling news: 


“The conclusion we’ve come to is that a significant spherical 2 aberration 3 appears to be present in the optics, in the optical telescope system optics,” he said. 


In other words - the outer edge of Hubble's primary mirror had been ground too flat, off by roughly one-fiftieth the thickness of a human hair. In 1993, a shuttle mission carried a replacement 4 camera, WFPC2 and an instrument with corrective lenses called COSTAR for astronauts to install on the telescope.


“The COSTAR inserted mirrors into the optical beam that corrected the light for all the other instruments,” said National Air and Space Museum senior curator David Devorkin. 


The fix proved that very difficult and very complicated operations could be undertaken by shuttle astronauts. 


“The whole idea of living and working in space is doing useful stuff and this certainly was useful," Devorkin said. "On the astronomical 5 side and you might say on the technical side, it represents how fast telescopes are improving because Hubble was only repaired once, but it was upgraded four times.”


COSTAR and WFPC2 were replaced in 2009 and are now on exhibit in the museum.  


Hubble images have become better and sharper over time, and its data has allowed astronomers 6 to confirm that the universe is expanding and calculate its age to some 13 to 14 billion years. 


And the powerful space telescope has led to other important breakthroughs. 


"… understanding star forming regions, how stars form out of gas and dust, and now the ability of the Hubble to see deeply into the infrared 7, far deeper than before has shown us the processes inside these interstellar clouds that literally 8 are forming the stars and their interaction with the dust and gas around them,” Devorkin said.   


As Hubble nears the end of its journey in space, the telescope has paved the way for its replacement. The James Webb Space Telescope - with an expected launch date in 2018 - will probe even farther beyond the spectrum 9 of light with a primary mirror five times larger than Hubble. 


“The James Webb is optimized 10 for infrared because all of the most amazing discoveries about galaxy 11 formation, star formation and the kind of stuff that astronomers want to know is in the infrared,” Devorkin said. 


No more service missions are scheduled for repairs or upgrades. Hubble's components 12 will slowly degrade to the point the telescope stops working. When that happens, the telescope will continue to orbit the Earth until its orbit decays, allowing it to spiral toward Earth. A robotic mission is expected to help de-orbit Hubble, guiding its remains 13 through a plunge 14 through the atmosphere and into the ocean, as its stellar career comes to an end.


But for now, as Hubble nears its 25th birthday next year, the telescope is still going strong. 


Astronomers hope it will last long enough for the James Webb Space Telescope to launch so that the two can be in space at same time and calibrate 15 with one another.  


Until its space journey comes to an end, Hubble remains a workhorse for astronomers and continues to delight the public with dazzling images.



1 remarkable
adj.显著的,异常的,非凡的,值得注意的
  • She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
  • These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。
2 spherical
adj.球形的;球面的
  • The Earth is a nearly spherical planet.地球是一个近似球体的行星。
  • Many engineers shy away from spherical projection methods.许多工程师对球面投影法有畏难情绪。
3 aberration
n.离开正路,脱离常规,色差
  • The removal of the chromatic aberration is then of primary importance.这时消除色差具有头等重要性。
  • Owing to a strange mental aberration he forgot his own name.由于一种莫名的精神错乱,他把自己的名字忘了。
4 replacement
n.取代,替换,交换;替代品,代用品
  • We are hard put to find a replacement for our assistant.我们很难找到一个人来代替我们的助手。
  • They put all the students through the replacement examination.他们让所有的学生参加分班考试。
5 astronomical
adj.天文学的,(数字)极大的
  • He was an expert on ancient Chinese astronomical literature.他是研究中国古代天文学文献的专家。
  • Houses in the village are selling for astronomical prices.乡村的房价正在飙升。
6 astronomers
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》
7 infrared
adj./n.红外线(的)
  • Infrared is widely used in industry and medical science.红外线广泛应用于工业和医学科学。
  • Infrared radiation has wavelengths longer than those of visible light.红外辐射的波长比可见光的波长长。
8 literally
adv.照字面意义,逐字地;确实
  • He translated the passage literally.他逐字逐句地翻译这段文字。
  • Sometimes she would not sit down till she was literally faint.有时候,她不走到真正要昏厥了,决不肯坐下来。
9 spectrum
n.谱,光谱,频谱;范围,幅度,系列
  • This is a kind of atomic spectrum.这是一种原子光谱。
  • We have known much of the constitution of the solar spectrum.关于太阳光谱的构成,我们已了解不少。
10 optimized
adj.最佳化的,(使)最优化的v.使最优化,使尽可能有效( optimize的过去式和过去分词 )
  • We are often asked whether consumer Web sites should be optimized for beginners or intermediates. 我们常常被问到这样的问题:消费类网站究竟应该为新手而优化,还是应该为中间用户而优化? 来自About Face 3交互设计精髓
  • GOOGLE Advertising optimized sequence, greatly increasing the advertising effect. 优化了GOOGLE广告位排列顺序,大大增加了广告效果。 来自互联网
11 galaxy
n.星系;银河系;一群(杰出或著名的人物)
  • The earth is one of the planets in the Galaxy.地球是银河系中的星球之一。
  • The company has a galaxy of talent.该公司拥有一批优秀的人才。
12 components
(机器、设备等的)构成要素,零件,成分; 成分( component的名词复数 ); [物理化学]组分; [数学]分量; (混合物的)组成部分
  • the components of a machine 机器部件
  • Our chemistry teacher often reduces a compound to its components in lab. 在实验室中化学老师常把化合物分解为各种成分。
13 remains
n.剩余物,残留物;遗体,遗迹
  • He ate the remains of food hungrily.他狼吞虎咽地吃剩余的食物。
  • The remains of the meal were fed to the dog.残羹剩饭喂狗了。
14 plunge
v.跳入,(使)投入,(使)陷入;猛冲
  • Test pool's water temperature before you plunge in.在你跳入之前你应该测试水温。
  • That would plunge them in the broil of the two countries.那将会使他们陷入这两国的争斗之中。
15 calibrate
校准;使合标准;测量(枪的)口径
  • Pesticide levels in food are simply too difficult to calibrate.食品中杀虫剂的含量很难精确测定。
学英语单词
-laik
A. S. A. R.
aldis lamp
aliphatic sesquiterpene
allocation of well rates
Anaplasma centrale
anomalous trichromat
appeals courts
arteriae mesenterica superior
astern moving blade
awshucks
Bacillus actinoides
balance pan
bigram
byte operand
capsicum annuum longums
carack
cider
Clematis pseudopogonandra
compulsory trust
creeper gear
d'oeuvres
Daily Cut-Off
dairy lactic acid bacterium
dendropathology
dichroic coating
distinguishing test
doctors of optometry
DQM
drongo
ecolinguistics
electric osmosis
family pezizaceaes
favorable trade balance
Filiouri
French Communist Party
gaussian response
gel test
gilboform
give countenance to
Gyobyu Res.
handing of results
harping on the same string
hectic flush
horse-fish
hum modulation factor
hydrostatic weighting
i-paied
ICRU
in fyll rig
keel strake
kroichick
latexed
Liceales
linkage
lutescens
market target
mathur
medfords
neatlines
Nirvanil
Nolvik
nutrient chemistry
ochterus marginatus
omophagias
operating voltage in a system
oxide film insulation
paramilitary organization
phisical network
podetium(pl.podetia)
polarization of polymer
pore mushroom
portuguese escudoes
prefinalization
Ptinidae
Ptychosperma
pythonesses
radiating matter
rami apicalis
Red Indian
reinitiation site
resegregrate
residual shim
resorptions
round strand wire ropes
sea gravel
sensitizing center
silver grays
simple probability
Smilax mairei
speechread
superior cerbellar veins
Svensk Filmindustri
Tebingtinggi, Pulau
tetras
theares
thermal infrared imager
thin shell structure
towerlet
weedkiller
winding arrangement
Windows event log