[MUSIC] How do we understand Earth? How is it evolved? How does it work? Fundamentally, we look at rocks. And that's what geologists do. By observing rocks, by figuring out what minerals they're made of, by determining their ages, we geologists deduce the processes that operate on the planet, and we piece together its geological history. This course presents Earth through the eyes of a geologist. You'll learn how to read the rocks. My name is Ed Monte, I'm a geologist at the American Museum of Natural History. I study lavas and other rocks that were once molten to understand Earth. >> Understanding Earth begins with observing it. In this course, you'll be doing just that. Early on, you'll use a digital camera and a notebook to make observations about a geologic feature in your area, and you'll develop the tools to read these rocks in order to piece together a small part of our planets history. I'm Ruth Kinsler and I'm the Senior Director for science education here at the American Museum of Natural History. >> We start with the concept of geologic time, a very difficult concept to master because of its enormity. But if we can master that concept and understand how to read the rocks, then we can peer into the distant past. For example, we'll travel back 3.8 billion years to discover an atmosphere that contained no oxygen. And then we'll follow the changes of that atmosphere through time. We'll discover that life had a profound influence in how the physical planet evolved. We'll visit the present day Earth and study its churning interior, which accounts for mountain belts and other large scale features on its surface. In short, we'll discover an Earth that is dynamic and changing. A machine, in essence, in the word of James Hutton more than 200 years ago. >> While you investigate this vast history, you'll also be exploring the local geologic feature in greater depth. Teachers find that this local geology activity helps students understand and appreciate the world around them. >> So, please join us. This is an exciting way to learn about Earth history. And in fact, to learn how geologists themselves learn that history. [MUSIC]