Astronomy is the scientific study of the universe as a whole, and of celestial bodies and the underlying physics governing these bodies. It is in some sense one of the oldest of the natural sciences, having been practiced by even very ancient civilizations, but it is also among the most modernized of the sciences, having extensively exploited both advances in technology and the rise of space exploration. The progress of technology has dramatically improved our understanding of the universe, revealing a richer tapestry than had ever been imagined before. This Wikibook introduces the advanced secondary or beginning university student to that tapestry and the process that revealed it to humanity, presenting astronomy not only as a field of knowledge, but also as a human endeavor in science.
Table of Contents 
- The Modern View of the Cosmos
- Observational Astronomy
- Motion and Gravity
- Principles of Light
- Planetary science
- Earth as a Planet
- Space Exploration
- Astrobiology and Extraterrestrial Life
- The Sun
- The Stellar Life Cycle
- Black Holes
- Gamma-Ray Bursts and Cosmic Rays
Also on Wikimedia 
Wikibooks is a Web site where this and other free textbooks are developed. In addition to this book, Wikibooks is the host of related textbook projects.
- General Relativity, an advanced undergraduate treatment of the principles of general relativity
- Astrophysics, a textbook for beginning students in physics and astronomy
- Astrodynamics, a look at the principles behind orbiting satellites
- Wikijunior:Solar System, a children's nonfiction book about the Solar System
- Messier Index, a list of all the deep-sky objects in the Messier Index.