the earth, moon, and sun are the most important things in our solar system. the sun is our source of light and heat with out it the world would freeze and plants could not grow. the sun is over 4.5 billion years old and the largest star in our solar system. the sun is 70% hydrogen, 28% helium, and 2% metal. the sun is 5,778k degrees hot meaning if you went to the sun you would burn. the earth is well known cause we live their, earth is the only planet provin to support life it has food, water, gravity, and oxygen. the moon orbits the sun and the earth, the moon is the only other planet besides earth to have had people on, if you look on the moon you will see a U.S.A flag put their by Neil Armstrong in 1966.