the atmosphere does not only protect the earth from the sun is radiation,but can also obstruct various space objects which are potentially harmful to lives on earth(e.g.asteroids and parts of comets).when these objects enter the earth is atmosphere,the friction will cause them to burn up.these falling objects are called meteors.on the contrary,if they also big that cannot burn up completely,they will impact the earth is surface.these objects impacting the earth is called meteorites.the atmosphere also helps us hear sounds when we speak and see the sun,the moon,and shining stars when we look up at the sky.