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Introduction to Astronomy (Lumen)

Introduction to Astronomy (Lumen)

Last updated

Jul 23, 2025
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- Detailed Licensing
- Front Matter

Lumen Learning
Lumen Learning

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This introductory astronomy textbook offers a comprehensive journey through the universe, beginning with foundational concepts and expanding outward to the farthest reaches of space and time. It starts by introducing basic celestial objects and the scale of the cosmos before guiding readers through the historical development of astronomy, from ancient skywatchers to modern scientific breakthroughs. Core chapters explore the motions of celestial bodies, the nature of light and spectra, and how telescopes extend our cosmic vision. The solar system is examined in detail, from rocky planets to gas giants, minor bodies, and the formation of planetary systems. The textbook then shifts focus to stars—their properties, life cycles, and dramatic endings—as well as galaxies, dark matter, and the structure of our Milky Way. It concludes with a deep dive into cosmology, including the Big Bang, the expansion of the universe, and humanity’s enduring questions about its origins and fate. Designed to build understanding progressively, the text blends scientific inquiry with observational tools, historical context, and current discoveries to foster a rich appreciation of the universe and our place within it.

Thumbnail: Colorful galaxy. (Unsplash License; Jeremy Thomas via Unsplash)

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