If small bits of stardust can become an enormous sun, can they also turn into a planet? Some people believe that when the sun was new and spinning, it took on the shape of an enormous whirling pizza with numerous lumps scattered throughout the dough. As the sun contracted, the outer parts of the pizza started to cool and separate and the lumps started to get bigger as they gathered more material from the leftovers. Have you ever watched a pizza maker spin a pizza as they were making it? When your parents place an order for pizza, see if you can come in early and watch this happen. If your parents make theirs at home, see if you can try your hand at learning how to spin one! Some scientists think that the sun burned away most of the gas that was around the lump that you know as Earth, leaving only rock and metal behind. Eventually dust that was created in the last moments of the other dying stars and mysterious balls of ice would bring to earth the materials it needed to sustain life. Their theory is that the oxygen created by volcanoes also combined with the hydrogen in the atmosphere causing continuous rain, which formed the oceans. After a long time, microscopic plants began to appear in the oceans and life on earth had begun. How do you think it all started?

Take a Look at That!

Have you ever watched a volcano erupt on a television program? All that red-hot liquid is coming from deep inside the earth! Do you know someone that has a lava lamp? They are fun to watch and they demonstrate how just a little heat can stir things up. The lamp's glass base contains wax and oil and the wax acts a lot like the lava in a volcano. There is a light bulb inside the bottom of the lamp that makes the wax melt and slowly float upward and then after it cools a little at the top of the lamp, itsinks to the bottom and then is heated again. There is also a lot of heat in a volcano. Have you ever warmed your hands by rubbing them together? Imagine if your hands were enormous chunks of rock, like pieces of the earth's surface, moving very slowly over, under, and around one another. These chucks of rock called tectonic plates are like huge islands that cover the face of the earth. It creates a lot of heat and lava when one plate is forced beneath its neighbor. They can flow through small cracks in the surface of the earth anywhere there is an opening. If this melted rock finds a big enough opening, it can create a fiery fountain called a volcano. Do you think the layers of melted rock that ooze out beneath the plates on the ocean floor would match the earth's magnetic field? They do, but scientists have found some of the layers show that the South Pole was once located in the ArcticOcean, which is now at the North Pole! They feel this discovery helps to prove that the earth has reversed its magnetic fields before, just like the sun does!

On the Move

Once in a while people will feel the ground move or hear dishes rattle in their cupboard. These movements are caused by the tectonic plates sliding against each other, causing earthquakes. Maybe you've tried tapping a glass or chunks of different kinds of metal to see what types of sounds they make. Scientists believe they can use the movement of waves from the earthquakes to show where the layers in the earth begin and end because each layer of the earth sends out a different type of wave. One way to think of the earth is like a peach. The crust or outer layer of the earth that you see every day is like the skin. Many scientists now think these earthquake waves show that under this outside layer is another layer of harder, heavier rock called the mantle, like the flesh of the peach; lava is formed in parts of this layer where the tectonic plates meet. Because there is so much pressure on the center of the earth, part of its iron core is a molten liquid. Way down in the middle of the earth is a solid metal core that is similar to the pit of a peach.