Planet Solar System
Our solar system is made of nine planets. Earth, Mercury, Mars, Uranus, Jupiter, Neptune, Venus, Saturn, and Pluto. Earth is home for all of us humans so we know quite a lot more about this planet than we do the others. Earth is the fifth largest planet and third from the sun. The top of the earth where we live is actually the smallest part of the planet and most of the mass is below the surface. Underneath where we live is a series of solid and separate plates that float above what is called the mantle. The earth's chemical composition is comprises of 34 % iron, 30 % oxygen, 15 % silicon, 13 % magnesium, 2 % nickel, and 2 % titanium. Mercury is a small planet, the eighth largest and the closet one to the sun. The temperatures on Mercury are wide in range from 90 to 700 degrees Kelvan. It is unlikely any life form could exist in this heat. Some scientists think that Mercury is simply a constant volanic eruption. ars holds the most mystique for humans since it our closet neighbor in the solar system. Recent unmanned probes of the surface of Mars have revealed a lot more about the Red Planet including photographs that are eerily similar to some places on earth. The other planets are either too far away or simply too obviously inhospitable to be of great interest to normal human beings. That hasn't stopped the scientists from continuing thie researh and investigation into our further off neighbors. Humans knew very little about the solar system until well into the 17th century when Gallileo developed the first telescope. Before that time the simple people of the earth either worshipped the sun and the moon and the stars or they thought that the earth was indeed the center of the universe. Only after bitter religious battles and the perescution of Gallileo and fellow eatly scientists like Copernicus did science achieve even a minor victory over ignoranace. Today massive laboratories monitor and direct cameras that stroll the surface of the moon and other planets with the ease that we drive our glof carts around the course.