There are four major areas in Earth science. Astronomy is the study of objects beyond Earth’s atmosphere. Meteorology is the branch of Earth science that deals with Earth’s atmosphere. The study of the materials that make up Earth and the processes that form and change these materials is known as geology. The study of Earth’s oceans is called oceanography.

• Earth can be divided into four main systems. The lithosphere includes the rocks that make up the crust and rigid, upper man- tle. The atmosphere is the blanket of gases that surrounds Earth. Earth’s hydrosphere is the system of all of the water on the planet. The biosphere is Earth’s inhabitants and their environments.

• All of Earth’s systems interact. You are part of the biosphere

and you live on the crust, which is part of the lithosphere. You breathe the gases in that atmosphere and depend in many ways on the water in the hydrosphere.

Earth Science 1.1