书城教材教辅用美国小学课本学英语
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第16章 Science科学常识(4)

卡车司机们忙着驾驶装满燃料的大卡车,这些燃料要往火箭中填充。加油是一件非常危险的工作,因为燃料非常容易爆炸,而火箭又需要非常多的燃料来完成一次长途旅行。正因为这项工作如此危险,所以通常在发射之前才会给火箭添加燃料。

工程师的工作是确定火箭运行的方向。他们为火箭绘制出一条空中路径,正如你可能会为自己的大沼泽地之行制定计划一样。工程师们必须确定火箭运行的速度以及需要携带多少燃料,他们可以通过电脑帮他们完成工作。

技术人员会对火箭进行技术检查,以确保它们真的准备就绪。其他技术人员会在屏幕上观看火箭的飞行,并检查其速度和方向。在航天中心,技术人员有许多工作要做。许多专家在火箭发射防护室中工作,他们通过特殊的屏幕观察火箭,因为火箭发射防护室没有窗户。

建筑工人在航天中心周围建成了许多建筑。他们中的一些人建造连接架,这个连接架是一个塔,火箭将在那上面被检查。其他人要按照轨道移动连接架,在火箭发射之前,他们要把它推到指定的停靠区域。挪动连接架的目的,是为了避免它被火箭点火时产生的高温烧坏。

制造运载火箭、卫星、太空船,这需要许多工人,这些事情往往在国家的其他地区完成。然后他们会用大卡车把这些东西运送到航天中心。到达之后,他们就和其他工作人员组成团队一起工作。

发射一枚火箭,需要许多人的共同努力。很多人愿意用大脑和双手勤奋工作,使艰难的工作变得容易一些。

练习

Ⅰ.选出正确答案填空。

1.航天中心的科学家们研究     。

空间       儿童       道路

2.     在火箭发射防护室中。

连接架      火箭       控制人员

3.支架是一种用来     的塔。

建造       检查       出售

4.火箭发射防护室没有     。

工人       屏幕       窗户

5.发射     需要许多人同心协力。

火箭       风暴       塔

6.火箭携带了大量     。

石块       星星       燃料

Ⅱ.将工作人员和他们的工作内容用线连起来。

1.科学家 a.运输燃料

2.卡车司机 b.为火箭绘制路径

3.工程师 c.通过屏幕观察火箭

4.气象人员 d.建造发射塔和建筑

5.技术人员 e.研究空间

6.支架工人 f.观测风暴

7.建筑工人 g.移动连接架到指定地点

Ⅰ.1.space 2.controls 3.checked 4.windows 5.rocket

6.fuel

Ⅱ.1.e 2.a 3.b 4.f 5.c 6.g 7.d

05 The Zodiac 黄道十二宫

The zodiac is a band of constellations that the Sun travels through in its annual trip around the sky. As the Earth travels around the Sun once a year, it looks like the Sun travels around the sky. The Sun travels through the 13 constellations, not just the 12 most people think of, and these are the constellations of the zodiac. The Moon and planets also stay within this band most of the time. The constellations of the zodiac are well known because the Sun, Moon, and planets travel through them, but many of them are minor constellations that contain no bright stars.

Have you ever heard the song “The Age of Aquarius”? Well, the true Age of Aquarius will begin in about 600 years, when, for the first time, the Sun will be in Aquarius on the first day of spring.

Aries

Aries is a large constellation with only three medium-bright stars in its northern part. These three stars form a simple pattern that is easy to recognize, but—despite its fame as a member of the zodiac—the constellation is not very interesting to observe. Aries is in the east in the autumn and high overhead in late December and January.

In Sumerian times, these stars were a “day laborer” who plowed a field to plant grain. It has been called a ram since at least the time of the ancient Greeks.

Four thousand years ago, the Earth was oriented so that the Sun was in Aries on the first day of spring, March 22, a day that then was considered the first day of the year. At that time, the Sun’s position was called the “first point of Aries.” The Sun is now in Pisces on the first day of spring, but Aries is still called the first constellation of the zodiac in memory of this ancient alignment. When any planet is “visiting” Aries, the planet is brighter than any of the constellation’s stars.

Cancer

Cancer is one of the faintest constellations of the zodiac. If it weren’t for its membership in the zodiac, few people would have heard of it. It has no bright stars.

Cancer is midway between the major constellations Leo and Gemini. It is in the early evening sky from February through May. In Greek mythology, Cancer was a crab that was sent to bite Hercules. Hercules squashed it easily. Ancient Egyptians saw it as a scarab beetle, the Babylonians may have seen it as a turtle, and on some old star maps it was a lobster!

Libra

Libra is a box of four medium-bright stars to the right of Scorpius, resembling a diamond. It is at its best spot for viewing in the early summer, when it is in the southern sky.

Libra is a set of balance scales that work by balancing two pans hanging from a lever, like the scales of justice seen on court buildings. The Sumerians may have originally called these stars scales because the Sun was in front of these stars on the first day of autumn, when day and night are balanced in length.

Libra is the only constellation in the zodiac that isn’t an animal. The stars of Libra were once seen as claws that belonged to Scorpio to the east. If you look at the Scorpion carefully, it is missing its claws. While it may make more sense for Libra’s stars to be Scorpion’s claws, ancient astronomers who wanted to divide the zodiac into 12 equal parts borrowed these stars to form a separate constellation.

Taurus

Taurus is one of the major constellations of the winter sky. It contains three bright stars and—even more importantly—two very bright star clusters. The Bull is above and to the right of Orion the Hunter, who is fighting the Bull and driving it westward across the sky.

Taurus looks like the front end of a giant bull.

Leo

Leo is a major constellation that is best seen in the springtime. The first appearance of Leo in the evening sky in March announces that spring is coming, and the Lion remains in the evening sky through June. It is one of the few constellations that can be made to look like what it is named after. Leo is Latin for “lion” and is one of the zodiacal constellations. Regulus, Leo’s A brightest star, is Latin for “Little King.”

Few of us see lions today except at the zoo, but to ancient Sumerians 5,000 years ago, lions were familiar predators who ventured down to the river valleys during hot summer days and hunted sheep and goats. These stars have been seen as a lion since those prehistoric days.

Scorpio

The Scorpion, a member of the zodiac, is a major constellation in the summer sky. From the United States, it is low on the southern horizon, where we lose much of its splendor. Far south of the equator, where it passes overhead, it is a magnificent group of bright stars.

Scorpio truly looks like a scorpion, and people have been calling it the Scorpion since prehistoric times—at least 6,000 years.

Scorpio now has only three stars for stubby claws, but long ago the claws included the stars of Libra, to the right.

In Greek mythology, Scorpio was the enemy of Orion. Orion died from the scorpion’s bite. Both he and the scorpion were placed in the sky, but on opposite sides, so one sets while the other rises.

The Milky Way runs through Scorpio. Like Sagittarius, it is filled with star clusters that are visible through binoculars or a small telescope. Two star clusters, M6 and M7, are bright enough to see without binoculars. They lie between the Scorpion’s stinger and the western end of Sagittarius.