1、Unit 4 Astronomy: the science of the starsPart 2: Teaching Resources(第二部分：教学资源)Section 1: A text structure analysis of HOW LIFE BEGAN ON THE EARTH1. Type of writing and summary of the textType of writing This is a descriptive writing.Main idea of the passage The earth came into being after the “Big
2、Bang”. Then small plants came growing in the water, followed by green plants appearing on land. In the end appeared small clever animals.Topic sentence of 1st paragraph After the “Big Bang”, the earth was just a cloud of energetic dust.Topic sentence of 2nd paragraph The earth was different because
3、of the arrival of small plants growing in the water.Topic sentence of 3rd paragraph Many millions of years later the first green plants began to appear on land.Topic sentence of 4th paragraph Small clever animals appeared and spread all over the earth.2. A tree diagramAfter the “Big Bang”, the earth
4、 being just a cloud of energetic dust.the arrival of small plants wing in the watergreen plants beginning to appear on landSmall clever animals appearing and spreading all over the earth.Section 2: Background information for Unit 4 Astronomy: the science of the stars1. THE PLANETS 行星Although we live
5、 in a very small piece of the Universe, its still where we call home and its a very interesting place. The nine planets that make up our solar system range from very tiny rocky planets to huge gas giants featuring fascinating ring systems. Mercury 水星Mercury is the closest planet to the Sun. Its surf
6、ace has many thousands of impact craters as a result of being bombarded by objects since the solar systems early days. Since Mercury has no protective atmosphere, the temperature on the surface ranges from extremely hot on the side facing the Sun to extremely cold on the side that faces away from th
7、e Sun. Venus 金星（太白星）Venus is named after the Roman goddess of love and beauty. This is one of those cases where beauty is only skin deep, though, as the surface of Venus is a very unpleasant place featuring very high temperatures, winds that blow hundreds of miles per hour and an atmosphere of sulfu
8、ric acid. Venus is an example of runaway greenhouse effect on a planetary scale. Earth 地球People always say theres no place like home. Our home planet is a very beautiful place with the most varied surface in the entire solar system. From a distance, our planet looks like a beautiful big blue marble.
9、 Mars 火星 The Red Planet is named after the Roman god of war. Its distinctive rust color is easily seen through a small telescope. The surface of Mars features many mountains, canyons and even polar ice caps that look a lot like those here on Earth. In ancient times, Mars may have harbored some kind
10、of life, and there is a lot of research going on now trying to get a definitive answer as to whether we are the only life forms in the solar system. Jupiter 木星Jupiter is the largest planet in our solar system. It has at least sixty-one moons and features the Great Red Spot, which is a huge “storm“ t
11、hat has been observed from here on Earth for over three hundred years. Saturn 土星Saturn is one of the most beautiful planets in the solar system. Its fascinating system of rings have been a source of wonder since we first saw them with the earliest telescopes. Although the rings look fairly simple th
12、rough a small telescope, spacecraft pictures have revealed that what looks like two rings through a telescope is actually hundreds of individual ring systems. In addition, Saturn has so many moons that it is like a miniature solar system. Uranus 天王星Uranus is one of the giant gas planets in the solar
13、 system. Its mysterious blue-green color provides very few clues as to what is going on underneath the surface clouds. Uranus also has a very faint ring system that we didnt know existed until the planet was visited by the Voyager spacecraft. Neptune 海王星Neptune was the last stop the Voyager mission
14、made before if left our solar system. What we found out from Voyager was that Neptune has winds that blow hundreds of miles per hour and a moon that features “geysers“ of nitrogen that erupt and leave dark marks on the surface. Pluto 冥王星Pluto is the smallest and most mysterious planet in our solar s
15、ystem. Pluto is so far away that the Sun is just a dim point of light that looks a lot like any other star. Pluto has one moon, Charon, that is almost as big as the planet itself. 2. The Big Bang Theory 大爆炸理论 The Big Bang Theory is the dominant scientific theory about the origin of the universe. Acc
16、ording to the big bang, the universe was created sometime between 10 billion and 20 billion years ago from a cosmic explosion that hurled matter and in all directions. In 1927, the Belgian priest Georges Lemaire was the first to propose that the universe began with the explosion of a primeval atom.
17、His proposal came after observing the red shift in distant nebulas by astronomers to a model of the universe based on relativity. Years later, Edwin Hubble found experimental evidence to help justify Lemaires theory. He found that distant galaxies in every direction are going away from us with speed
18、s proportional to their distance. The big bang was initially suggested because it explains why distant galaxies are traveling away from us at great speeds. The theory also predicts the existence of cosmic background radiation (the glow left over from the explosion itself). The Big Bang Theory receiv
19、ed its strongest confirmation when this radiation was discovered in 1964 by Arno Penzias and Robert Wilson, who later won the Nobel Prize for this discovery. Although the Big Bang Theory is widely accepted, it probably will never be proved; consequentially, leaving a number of tough, unanswered questions.
