【英語時間】Our home in the universe
發佈時間：07:00 2021-05-17
We do not know much about space, and what we do know has fascinated us. Try and learn a little about Earth and its place in the solar system.
Earth
This is the third of the eight planets in the solar system. It is the only planet in the solar system to have enough liquid water so that life can exist on it. NASA and other space agencies are worried about asteroids, or giant space rocks, hitting us because scientists believe it has happened before and is what made the dinosaurs go extinct.
Planets
Planets are celestial bodies orbiting around a star. It has to round, not big enough to start giving out light on its own, and not have anything blocking its elliptical path around the star. The word 'planet' is old and comes from ancient Greek（古希臘文）. Most planets we know, be they in the solar system or out, are billions of years old. This includes Earth.
The solar system
The solar system is the phrase we use to describe the star system we live in. At the centre is the Sun, and then there are the eight planets. The first four planets - Mercury, Venus, Earth and Mars - are rocky planets, but Jupiter and Saturn are gas giants. Then come Neptune and Uranus, both of which are ice planets. Between Mars and Jupiter is a ring of asteroids called the asteroid belt.
Vocabulary
fascinate (v) 迷住
solar system (n phr) 太陽系
asteroid (n) 小行星
celestial body (n phr) 天體
orbit (v) 繞...運行
elliptical (adj) 橢圓的
原文刊於2020年10月1日#541親子王
