Words to Know
science, earth science, atmosphere, hydrosphere, lithosphere, crust, mantle, core, planet, solar system. galaxy
Have you ever wondered where rain water goes when it seeps into the ground? Have you thought about how old water is? Or, what happens to it when it evaporates. These are questions that scientists try to answer. Science is the search for answers to questions about the creation.
Learning about Earth Science which is the search for answers to questions about earth, will help you discover some of these answers.
Satellites are circling the earth right now as we speak, taking pictures to unlock mysteries about the earth's surface. Scientists use satellite pictures to find minerals, track storms, and to develop maps. In this chapter, students discover some of the ways scientists go about their search for knowledge of the earth.
Scientists spend only a portion of their time researching the earth's surface. They also study the processes that take place around the earth and within its atmosphere. Take a look up at the sky, you will see the earth's atmosphere. The atmosphere is the blanket of air that surrounds the earth. The blanket is a very thin layer of gases, oxygen and nitrogen. It also includes water, ice, dust, and other particles.
Our water supply covers seventy percent of the earth's surface. It is known as the hydrosphere. The hydrosphere includes the salt water in oceans, and the fresh water found in lakes and rivers. These bodies of water behave differently, but they both sink into the ground and rise into the atmosphere.
Land is the solid outermost part of earth known as the lithosphere. The lithosphere varies in degree of depth and includes mountains, hills, and valleys. You can also find a part of the interior of the earth within the lithosphere.