IntroductionofSolarSystem(太阳系八大行星介绍)

1、Made by Elsa Ren Our solar system is nearly five billion years old. It is made up of planets, dwarf planets, and more than 170 moons, as well as dust, gas, and thousands of asteroids and comets, all orbiting around a central sun.Solar systemSUN（太阳）（太阳）Every object in the solar system revolves around

2、 this “average” star that makes up about 99% of the systems total mass. Without energy from the sun, life would not be possible on Earth.Mercury（水星）（水星）With Plutos demotion to dwarf planet, Mercury became the solar systems smallest planet. Its heavily cratered surface resembles that of Earths moon.V

3、enus（金星）（金星）Venus is similar to Earth in size and mass, but its atmosphere is primarily carbon dioxide. A permanent blanket of clouds traps heat, creating surface temperatures hot enough to melt lead.Earth（地球）（地球） Earth in its history, Earth looked much like its rocky neighbors Mercury, Venus, and M

4、ars. But its atmosphere, distance from the sun, and countless other variables turned Earth into a haven for life. Mars（火星）（火星）Vast networks of canyons and riverbeds on the red planet have led scientists to hypothesize it once supported a wet, warm, Earthlike climate.Jupiter （木星）（木星）The largest plane

5、t in our solar system is the first of the so-called gas giants. Made mostly of hydrogen and helium, Jupiter has no solid surface. Its bands of colorful clouds are created by high-speed jet streams.Saturn（土星）（土星）Gliding across the night sky, Saturn is among the most graceful sights in the solar syste

6、m. The earliest telescope observers were dazzled by its ringsonce thought to be the only ones among the planets, but not known to be common to all the gas giants.Uranus（天王星）（天王星）Third of the gas giants from the sun, Uranus appears to glow blue-green in the dim sunlight as methane in its upper atmosp

7、here absorbs red light waves.Neptune（海王星）（海王星） The outermost gaseous planets blue hue comes from methane in its outer layer, which is also made up of a mixture of heated hydrogen, helium, and water.Pluto（冥王星）（冥王星）In 2006, petite Pluto was stripped of its planet status and downgraded to a dwarf planet. But its still on NASAs radar the space agency plans to explore Pluto in 2015.Review最小的行星Mercury（水星）唯一一颗没有磁场的行星Venus（金星） 自转最快的行星Jupiter（木星）密度最小的行星Saturn（土星） ReviewMer