1: Introduction to Astronomy
- Page ID
- 113013
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Astronomy is defined as the study of the objects that lie beyond our planet Earth and the processes by which these objects interact with one another. We will see, though, that it is much more. It is also humanity's attempt to organize what we learn into a clear history of the universe, from the instant of its birth in the Big Bang to the present moment. Throughout this book, we emphasize that science is a progress report, one that changes constantly as new techniques and instruments allow us to probe the universe more deeply.
By the end of this section, you will be able to:
- Describe early examples of astronomy around the world
- Describe geocentric model of the universe
- Describe the heliocentric model of the Solar System
- Explain Kepler’s three laws of planetary motion
- Explain the strength of gravity is related to mass and distance
Thumbnail: Silhouette of a person standing in foreground of a black, orange, and blue sunrise-or-sunset horizon in Montana. ("Silhouette person standing with horizon (Unsplash)," Jay Dantinne jayd, CC0 via Wikimedia Commons)

