1、返回导航Unit 4 Astronomy：the science of the stars 返回导航1 学习目标展示 2 背景知识链接 返回导航学 习 目 标 展 示返回导航类别课程标准要求掌握的项目话题Science of the stars；the development of life；space travel and gravity词汇astronomy system religion theory atom billion globe violent carbon atmosphere unlikefundamental harmful acid chain multiply oxy
2、gen exist thus dioxide puzzle biology biologistgravity satellite gentle physicist climate crash spaceship pull floatsolar system in time lay eggs give birth to in ones turn carbon dioxide prevent.from block out cheer up now that break out watch out for返回导航类别课程标准要求掌握的项目功能指示(Instructions)Please pay at
3、tention to.Please check that.Please look at.Make sure that.Dont forget to.Watch out for.You need.Youd better.You must/mustnt.返回导航类别课程标准要求掌握的项目语法主语从句(Noun clauses as the subject)What it was to become was uncertain until between 4.5 and 3.8 billion years ago when the dust settled into a solid globe.it
4、 was not clear whether the shape would last or not.What is even more important is that as the earth cooled down，water began to appear on its surface.It was not immediately obvious that water was to be fundamental to the development of life.What many scientists believe is that the continued presence
5、of water allowed the earth to dissolve harmful gases and acids into the oceans and seas.Why they suddenly disappeared still remains a mystery.So whether life will continue on the earth for millions of years to come will depend on whether this problem can be solved.How life began on earth is one of t
6、he biggest puzzles that scientists found hard to solve.返回导航背 景 知 识 链 接返回导航Astronomy is the oldest science known to man.Thousands of years ago manlooked at the stars and wondered about the heavens.But man was limited by the sixplanets that he could see with his eyes alone.The Greeks studied astronomy
7、 over 2,000years ago.They could see the size，colour，and brightness of a star.They could see itsplace in the sky.They watched the stars move as the seasons changed.But the Greekshad no tools to help themselves study the heavens.Each new tool added to the field ofastronomy helped man reach out into sp
8、ace.Until there were telescopes，man knewa little about the moon.He did not know that the planet called Saturn had ringsaround it.His sight was so limited that he could not see all the planets.返回导航In the early 1700s，people thought there were only six planets.Before thespectroscope，man did not know wh
9、at kind of gases is around the sun or otherstars.Without the radiotelescope，we did not know that radio noises come from farin space.Today，astronomy is a growing science.We have learned more in the lastfifty years than in the whole history of astronomy.返回导航天文学是人类已知的最古老的科学。几千年前，人类仰望星辰，对天空充满了好奇。但那时人类仅仅
10、知道他们眼睛所看见的六颗行星。希腊人在2 000 多年前开始研究天文学。他们能看到星体的大小、颜色及亮度。他们能看到它在天空中的位置。他们观察到星体随着季节的改变而移动。但是希腊人没有工具帮助他们研究星空。天文学领域每一种新工具的出现都帮助人类向太空深处探索。直到有了望远镜，人类对月球才有所了解。人类当时不知道被称为土星的行星周围有光环。返回导航人类的视野非常有限，看不到所有的行星。在18世纪早期，人们认为只有六颗行星。在分光镜出现之前，人类不知道太阳或其他星球周围有什么样的气体。没有射电望远镜，我们不知道射频噪音来自遥远的太空。如今，天文学是一门日益发展的科学。我们在过去的50年里所了解的要比在整个天文学史上所了解的还要多。返回导航Notestelescope n望远镜 Saturn n土星 spectroscope n分光镜 radiotelescope n射电望远镜TaskAccording to the passage，what helped human beings observe the moon?The appearance of the telescopes返回导航
