Directions: You are expected to study this section in class. Don’t preview.

1. Word Pretest

For each italicized word or phrase, choose the best meaning below.
1. The report takes a global view of the company’s problems.
　A. planetary
　B. worldwide
　C. comprehensive
2. The Apollo mission made an enormous contribution to our understanding of the moon.
　A. task
　B. special journey
　C. delegation
3. You should know the topography of your city.
　A. surface features
　B. location
　C. population
4. They decided to step up reconnaissance of enemy navy movements.
　A. process of obtaining information about
　B. process of obstructing
　C. process of having control over
5. The two subjects will be studied concurrently.
　A. at different time
　B. at the same place
　C. at the same time
6. Hero stories infused patriotisms into the hearts of the young students.
　A. filled  
　B. soaked
　C. melted
7. The commander made a detailed study of the terrain.
　A. may
　B. area of land
　C. position
8. The platoon leader deployed his men on both sides of the road.
　A. placed
　B. ordered
　C. led

2 Text
2.1Cultural Background

火星为距太阳第四远，也是太阳系中第七大行星：

    火星(希腊语: 阿瑞斯)被称为战神。这或许是由于它鲜红的颜色而得来的；火星有时被称为“红色行生”。（趣记：在希腊人之前，古罗马人曾把火星人微言轻农耕之神来供奉。而好侵略扩张的希腊人却把火星作为战争的象征）而月份三份的名字也是得自于火星。
    火星在史前时代就已经为人类所知。由于它被认为是太阳系中人类最好的住所（除地球外），它受到科幻小说家们的喜爱。
    第一次对火星的探测是由水手4号飞行器在1965年进行的。人们接连又作了几次尝试，包括1976年的两艘海盗号飞行器（左图）。此后，经过长达20年的间隙，在1997年的七月四日，火星探路者号终于成功地登上火星（右图）。
    火星的轨道是显著的椭圆形。因此，在接受太阳照射的地方，近日点和远日点之间的温差将近30摄氏度。这对火星的气候产生巨大的影响。火星上的平均温度大约为218K（-55℃，-67华氏度），但却具有从冬天的140K（-133℃，-207华氏度）到夏日白天的将近300K（27℃，80华氏度）的跨度。尽管火星比地球小得多，但它的表面积却相当于地球表面的陆地面积。
除地球，火星是具有最多各种有趣地形的固态表面行星。其中不乏一些壮观的地形：
－ 奥林匹斯山脉： 它在地表上的高度有24千米（78000英尺），是太阳系中最大的山脉。它的基座直径超过500千米，并由一座高达6千米（20000英尺）的悬崖环绕着（右图）；
－ Tharsis: 火星表面的一个巨大凸起，有大约4000千米宽，10千米高；
－ Valles Marineris: 深2至7千米，长为4000千米的峡谷群（标题下图）；
－ Hellas Planitia: 处于南半球，6000多米深，直径为2000千米的冲击环形山。
火星的表面有很多年代已久的环形山。但是也有不少形成不久的山谷、山脊、小山及平原。
    在火星的南半球，有着与月球上相似的曲型的环状高地（左图）。相反的，它的北半球大多由新近形成的低平的平原组成。这些平原的形成过程十分复杂。南北边界上出现几千米的巨大高度变化。形成南北地势巨大差异以及边界地区高度剧变的原因还不得而知（有人推测这是由于火星外层物增加的一瞬间产生的巨大作用力所形成的）。最近，一些科学家开始怀疑那些陡峭的高山是否在它原先的地方。这个疑点将由“火星全球勘测员”来解决。
    火星的内部情况只是依靠它的表面情况资料和有关的大量数据来推断的。一般认为它的核心是半径为1700千米的高密度物质组成；外包一层熔岩，它比地球的地幔更稠些；最外层是一层薄薄的外壳。相对于其他固态行星而言，火星的密度较低，这表明，火星核中的铁（镁和硫化铁）可能含带较多的硫。
    如同水星和月球，火星也缺乏活跃的板块运动；没有迹象表明火星发生过能造成像地球般如此多褶皱山系的地壳平移活动。由于没有横向的移动，在地壳下的巨热地带相对于地面处于静止状态。再加之地面的轻微引力，造成了Tharis凸起和巨大的火山。但是，人们却未发现火山最近有过活动的迹象。虽然，火星可能曾发生过很多火山运动，可它看来从未有过任何板块运动。
    火星上曾有过洪水，地面上也有一些小河道（右图），十分清楚地证明了许多地方曾受到侵蚀。在过去，火星表面存在过干净的水，甚至可能有过大湖和海洋。但是这些东西看来只存在很短的时间，而且据估计距今也有大约四十亿年了。（Valles Marneris不是由流水通过而形成的。它是由于外壳的伸展和撞击，伴随着Tharsis凸起而生成的）。
    在火星的早期，它与地球十分相似。像地球一样，火星上几乎所有的二氧化碳都被转化为含碳的岩石。但由于缺少地球的板块运动，火星无法使二氧化碳再次循环到它的大气中，从而无法产生意义重大的温室效应。因此，即使把它拉到与地球距太阳同等距离的位置，火星表面的温度仍比地球上的冷得多。
    火星的那层薄薄的大气主要是由余留下的二氧化碳（95.3％）加上氮气（2.7％）、氩气（1.6％）和微量的氧气（0.15％）和水汽（0.03％）组成的。火星表面的平均大气压强仅为大约7毫巴（比地球上的1％还小），但它随着高度的变化而变化，在盆地的最深处可高达9毫巴，而在Olympus Mons的顶端却只有1毫巴。但是它也足以支持偶尔整月席卷整颗行星的飓风和大风暴。火星那层薄薄的大气层虽然也能制造温室效应，但那些仅能提高其表面5K的温度，比我们所知道的金星和地球的少得多。
    火星的两极永久地被固态二氧化碳（干冰）覆盖着。这个冰罩的结构是层叠式的，它是由冰层与变化着的二氧化碳层轮流叠加而成。在北部的夏天，二氧化碳完全升华，留下剩余的冰水层。由于南部的二氧化碳从没有完全消失过，所以我们无法知道在南部的冰层下是否也存在着冰水层（左图）。这种现象的原因还不知道，但或许是由于火星赤道面与其运行轨道之间的夹角的长期变化引起气候的变化造成的。或许在火星表面下较深处也有水存在。这种因季节变化而产生的两极覆盖层的变化使火星的气压改变了25％左右（由海盗号测量出）。
    但是最近通过哈勃望远镜的观察却表明海盗号当时勘测时的环境并非是典型的情况。火星的大气现在似乎比海盗号勘测出的更冷、更干了（详细情况请看来自STScI站点）。
    海盗号尝试过作实验去决定火星上是否有生命，结果是否定的。但乐观派们指出，只有两个小样本是合格的，并且又并非来自最好的地方。以后的火星探索者们将继续更多的实验。
    一块小陨石（SNC陨石）被认为是来自于火星的。
    1996年8月6日，戴维·朱开(David McKay) 等人宣称，在火星的陨石中首次发现有有机物的构成。那作者甚至说这种构成加上一些其他从陨石中得到的矿物，可以成为火星古微生物的证明。（左图？）
    如此惊人的结论，但它却没有使有外星人存在这一结论成立。自以戴维·朱开发表意见后，一些反对者的研究也被发布。但任何结论都应当“言之有理，言之有据”。在没有十分肯定宣布结论之前仍有许多事要做。

    在火星的热带地区有很大一片引力微弱的地方。这是由火星全球勘测员在它进入火星轨道时所获得的意外发现。它们可能是早期外壳消失时所遣留下的。这或许对研究火星的内部结构、过去的气压情况，甚至是古生命存在的可能都十分有用。
    在夜空中，用肉眼很容易看见火星。由于它离地球十分近，所以显得很明亮。迈克·哈卫的行星寻找图表显示了火星以及其它行星在天空中的位置。越来越多的细节，越来越好的图表将被如星光灿烂这样的天文程序来发现和完成。

• 火星上的“脸”

火星的卫星

火星有两个小型的近地面卫星。

未知点

• 为什么火星的南北近日点处有如此大的差别？为什么其近南北极处的大气罩不同？
• 在火星上仍有活火山吗？
• 是什么使火星上的被侵蚀处的形态与地球上的河床如此相似？
• 火星上有多少地下水？
• 火星被认为是最可能存在生命的行星列表中的头一个。“海盗号”没有发现其上有生命的迹象。但是他们只测试了两个独立的区域。其他未测的区域是否会有生命，异或是在过去的某个时候火星上曾存在生命？最近有关陨石的证据还需确定。多次的勘测研究会带来结果的。
• 探索火星的前景较之其他行星尤为乐观。NASA的火星全球勘测者号载着许多从不幸的火星观察者号中拿来的科学仪器，正运行在它的轨道上工作。火星探路者号携带的登陆机于1997年7月4日成功地登上火星。（第三批探索者，俄罗斯的火星 96, 在升空时失败）。一些其他的探索计划在1998年实行，但在俄罗斯，甚至在美国，资金仍是一个大问题。1995年的火星观察者号的提案未被国会通过；没有人能预言未来探测任务的政治性。最初的俄罗斯的火星 96（后又被称为火星 98）的计划已放弃了。现在日本正在为其名为“行星B”的火星探索任务进行计划；如果美国犹豫不决的话，或许他们会使用火箭来完成任务。

Return to the Red Planet

    　After 20 years, a U.S. spacecraft will again visit Mars. With the journey by Mars Global Surveyor, scheduled to launch in November 1996, the National Aeronautics and Space Administration (NASA) and the Jet Propulsion Laboratory (JPL) of the Californian Institute of Technology will continue the global explorations of the Red Planet begun in 1971 with the Mariner mission to Mars and carried on in the mid-1970s by the Viking mission. The Mars Global Surveyor spacecraft will travel hundreds of millions of kilometers to carry out an extensive study of Mars using its suite of sophisticated remote-sensing instruments. The goal is to create a global portrait of Mars by surveying the planet’s topography, magnetism, mineral composition, and atmosphere.
　　The exploration of Mars has been carried out in stages: reconnaissance, exploration, and intensive study. Reconnaissance was provided by the first flyby missions --- Mariners 4, 6, and 7 --- which took quick looks at small areas of Mars. Later exploratory missions of longer duration with the more complex Mariner 9 and Viking orbiters provided our first global information about the planet, while the two Viking landers focused on a special intensive study: the search for life on Mars. The two Viking Landers carried out the first direct search for life on the Red Planet. They dug up samples of the Martian soil, treated some of them with nutrients, and then tried to detect evidence of microscopic life forms. While analyses of the Viking data found no indications of biological processes, there is still a possibility that life exists somewhere else on the planet, and there may be organic matter or fossils that await detection. Although these missions made spectacular discoveries, many of the deepest questions about Mars remain unanswered.
　　By the early 1980s, it was clear that the next mission to explore Mars would have to be more comprehensive than anything done before. NASA and its scientific advisory committees agreed that long-term, global coverage of Mars was the essential next step. Such a mission should make a variety of observations over at least one complete Martian year, studying the surface, atmosphere, and interior. This could be done economically by a single spacecraft that would circle Mars in a nearly polar orbit, carrying a suite of instruments that would operate concurrently wile continuously examining the entire planetary environment.
　　The Mars Observer mission was developed to conduct the global studies needed to fill in many of the gaps in our understanding of the planet. Unfortunately, the Mars Observer spacecraft was lost in August 1993 just as it approached orbit insertion at the Red Planet. Mars Global Surveyor --- managed for NASA by JPL, an operating division of the California Institute of Technology --- will realize many of the science objectives that were not fulfilled by Mars Observer. The new mission’s science goals are to enhance the global understanding of the geology and climate of Mars. This will be accomplished by determining the composition, distribution, and physical properties of surface minerals, rocks, and ices; establishing the nature of the magnetic field; and studying surface-atmosphere interaction by monitoring surface features, polar caps, polar energy balance, atmospheric dust, and clouds over a seasonal cycle. This systematic, intensive global analysis makes Mars Global Survey one of the most exciting efforts undertaken in planetary exploration.
　　Mars Global Surveyor is the first venture in the NASA Mars Surveyor Program --- a new series of missions to explore the Red Planet. Over the ext decade, the Mars Surveyor Program will launch orbiters or landers every 25 months, using advanced technology to develop a comprehensive portrait of Mars. By studying Mars, scientists hope to better understand the formation and evolution of Earth and of the inner solar system. This effort , which will involve international participation and collaboration, is also expected to provide a basis for infusing science, mathematics, and engineering into our educational system.
　　In September 1997, the Mars Global Surveyor spacecraft, approaching Mars after a 10-month voyage from Earth, will fire its main rocket engine, slowing its journey and allowing itself to be captured by Mars’ gravity. The small spacecraft will then swing into an elliptical (highly elongated), near-polar orbit around the Red Planet. In the months that follow, thruster firings and aerobraking maneuvers, orchestrated by mission controllers hundreds of millions of kilometers away, will gradually reshape the spacecraft’s orbit into a nearly circular mapping path, 178 kilometers above the surface.
　　Once in its mapping orbit, Mars Global Surveyor will complete one orbit around Mars in about two hours. Each new orbit will bring the spacecraft over a different part of Mars. As the weeks pass, the spacecraft will create a global portrait of Mars --- capturing the planet’s ancient cratered plains, huge canyon system, massive volcanoes, gigantic channels, and frozen polar caps. During its mission, Mars Global Surveyor will pass over the terrain where the two inactive U.S. Viking lander have rested for 19 years.
　　As Mars rotate beneath the spacecraft, a suite of onboard instruments will record detailed information. Detectors will measure radiation from the surface to determine the minerals that make up Mars. These same instruments will record radiation from the thin Martian atmosphere, gathering data about its changing pressure, composition, water content, and dust clouds. The camera system will use wide- and narrow-angle components to record landforms and atmospheric cloud patterns. As the telecommunications subsystem transmits information back to Earth, engineers will use the signal of the orbiting spacecraft to derive data about the planet’s atmosphere and gravitation field.
　　Global mapping operations are scheduled to last two years. By the time these operations are over, Mars Global Surveyor will have obtained an extensive record of the nature and behavior of the Martian surface, atmosphere, and interior. Such a record will aid in planning more specialized explorations that might involve robots, scientific stations deployed to the Martian surface, perhaps even human landings. Just as important, this record will help us understand our own planet, Earth.
　　Mars may have a unique role in our future. Despite its distance from Earth and its harsh environment, it is the only other planet within our solar system where we can reasonably think that humans might someday walk, explore, or even live. Mars Global Surveyor and the automated mission s that follow it have a dual task: to learn as much as possible about the fascinating Red Planet and to collect the data that we must have if we are ever to journey to Mars and explore it firsthand.

Total Words: 1 080
Total Reading Time: _______

Reading Comprehension

Circle the letter of the best answer.
1. Which is the correct order for the exploration of Mars?
　A. The Viking mission, the Mariner mission, and Mars Global Surveyor.
　B. The Mariner mission, the Viking mission, and Mars Global Surveyor.
　C. Mars Global Surveyor, the Viking mission, and the Mariner mission.
2. The first direct search for life on Mars was carried out by _______.
　A. Mariner 9
　B. two Viking orbiters
　C. two Viking landers
3. Mars Global Surveyor is ________.
　A. managed by NASA
　B. managed by JPL for NASA
　C. managed by JPL for the California Institute of Technology
4. The science goals of Mars Global Surveyor include the following except ______.
　A. understanding Mars’ geology
　B. studying Mars’ climate
　C. finding the Mars Observer which was lost in 1993
5. The Mars Global Surveyor Program will launch orbiters or landers every ______.
　A. 15
　B. 20
　C. 25
6. Mars Global Surveyor will gradually get into its mapping orbit by ______.
　A. Allowing the spacecraft to be captured by Mars’ gravity
　B. thruster firings and aerobraking maneuvers
　C. firing the spacecraft’s main rocket engine
7. Global mapping operations are scheduled to last _______.
　A. 25 months
　B. one year
　C. two years
8. Which of the following statements about Mars is not true?
　A. Mars is hundreds of millions of kilometers away from Earth.
　B. Mars has massive volcanoes, gigantic channels, and frozen polar caps.
　C. Mars is the only planet within our solar system where we can reasonably think that humans might someday 　walk.

Key

Vocabulary Building

Definition

Define the following terms in your own words.
exploration
planet
orbit
the Arctic
Antarctica

Idiom

Complete the following sentences with appropriate idiomatic expressions which are related to the idea of EASE OF EFFORT. Make sure it fits the blanks.

　　　　be a breeze             have a green thumb
　　　　be easy as pie           have a golden touch
　　　　have two left feet        have a nose for something

1. Ann’s garden is beautiful. She can make anything grow. Her friend says she ______.
2. Understanding geometry is no problem for Frank. He thinks it _______.
3. Henry cannot dance very well at all. He is always tripping over his partner. Henry ______.
4. Jan made her first million dollars when she was only nineteen, People say she _______.
5. Bruce is a good newspaper reporter. He always seems to know where to go for the news. He _______.
6. Mary is very good at standing on her head. For her, it ______.

General Vocabulary Exercise
Use the appropriate form of the word given in the blankets to fill in the corresponding blank.
1. The ______ of marijuana does not prevent many people from using it. (legal)
2. He worked ______ to perfect his technical and improvisational skills. (ambition)
3. Unfortunately, such _____ practices often go unnoticed. (discriminate)
4. Henry Ford was a ______ individual who built one of America’s largest industries. (persist)
5. Because of this low ______ to cold, they can be seriously damaged when temperatures drop below freezing. (resistant)
6. ______ in the water and air can create serious health hazards. (contaminate)
7. He was surprised to discover that his driver’s license was ______; it had expired the previous week. (valid)
8. The water around the islands is _____ clear, giving underwater swimmers a great view of fish and rock formations. (fantasy)
9. The space program has strict requirements for its astronauts, _______, that they be in excellent physical and mental health. (specify)
10. Walt Disney’s movies and cartoons ______ children and grown-ups since 1926. (amusement)

Analogies

Select the lettered pair that beat expresses a relationship similar to that expressed in the original pair.
1. RETRACT: STATEMENT:
　A. substantiate: pledge            B. repeal: legislation
　C. reveal: promise               D. precipitate: procedure
2. DEPART: ABSCOND:
　A. store: secrete              B. cover: eclipse
　C. speak: harangue           D. intervene: interfere
3. FRUGAL: PENURIOUS:
　A. temperate: sober            B. ethical: unscrupulous
　C. cynical: sarcastic           D. compliant: obsequious
4. SOLDIER: ARMY
　A. element: compound         B. music: harmony
　C. ruler: height               D. negative: exposure
5. MARTIAL: MILITARY:
　A. basic: simplistic            B. classic: musical
　C. cosmic: planetary           D. runic: mysterious
6. UNDERSTUDY: STAR:
　A. patient: surgeon            B. deputy: sheriff
　C. secretary: executive         D. clerk: judge
7. LATENCY: RESPONSE:
　A. duration: process           B. incubation: disease
　C. interval: periodicity         D. fluctuation: equilibrium
8. ARTICULATE: SPEECH:
　A. meticulous: power          B. graceful: movement
　C. dissenting: thought          D. fawning: respect

Key

Cloze

Read through the following passage and then decide which of the choices given below would correctly complete the passage if inserted in the corresponding blanks.
　　At the bottom of the world lies a mighty continent still wrapped in the Ice Age and,   1          recent times, unknown to man.    2    of the continent is a complete blank on our maps. A      1 000-mile stretch of the coastline has never been    3   by any ship. Man has explored, on foot, less than one per cent of its area.
　　Antarctica differs fundamentally   4    the Arctic regions. The Arctic is an ocean, covered with drifting    5   and surrounded by the land masses of Europe, Asia, and North America. The Antarctic is a continent almost as large as Europe and Australia  6  , centered roughly on the South Pole   7   surrounded by the most unobstructed water areas of the world --- the Atlantic, Pacific, and Indian Oceans.
　　The continent ice sheet is more than two miles  8  in its center; the air over the Antarctic is much colder than it is   9   the Arctic regions. More than a million persons live within 2 000 miles of the North Pole in an area that    10   most of Alaska, Siberia, and Scandinavia --- a region rich   11   forest and mining industries. Apart from a handful of weather stations, within the same distance of the South Pole there is not a single tree, industry, or settlement.

1. A. until        B. before       C. in            D. since
2. A. Much       B. Many       C. Most          D. Little
3. A. landed      B. reached      C. attacked       D. accompanied
4. A. in          B. at         C. from          D. with
5. A. land        B. area       C. continent       D. ice
6. A. combined   B. combining  C. combine        D. combines
7. A. when       B. but        C. so            D. and
8. A. tall         B. high       C. deep          D. low
9. A. on         B. within      C. over          D. at
10. A. includes    B. including   C. included       D. include
11. A. of         B. on        C. with           D. in

key