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  1. Ch. 1 Introduction - Astronomy 2e | OpenStax

    This free textbook is an OpenStax resource written to increase student access to high-quality, peer-reviewed learning materials.

  2. Introduction to Astronomy | Physics | MIT OpenCourseWare

    Introduction to Astronomy provides a quantitative introduction to the physics of the solar system, stars, the interstellar medium, the galaxy, and the universe, as determined from a variety of astronomical …

  3. Astronomy 101: The Basics of Learning Astronomy - ThoughtCo

    May 6, 2025 · Learn the basics of astronomy and how it helps scientists understand everything from planets and moons to galaxies and the structure of the universe.

  4. Introduction to Astronomy (Lumen) - Physics LibreTexts

    This textbook offers a broad introduction to astronomy, covering the structure and scale of the universe, the history of astronomical discovery, the motions of celestial bodies, light and telescopes, …

  5. Astronomy | Definition, History, Discoveries, & Facts | Britannica

    Nov 14, 2025 · Astronomy, science that encompasses the study of all extraterrestrial objects and phenomena. Since the late 19th century, astronomy has expanded to include astrophysics, the …

  6. What is Astronomy? | AMNH

    Astronomy is the study of everything in the universe beyond Earth’s atmosphere. That includes objects we can see with our naked eyes, like the Sun , the Moon , the planets, and the stars .

  7. Introduction to Astronomy

    Nov 26, 2021 · In the following chapters you will learn how astronomers measure the distances, sizes, and ages of these objects and determine what they are like and what makes them appear the way …

  8. Module IntroductionIntroduction to Astronomy

    Astronomy is a passion for many and today is a mainstream hobby, as in years past. Introduction to Astronomy will provide you with an opportunity to explore both the significant historical aspects of …

  9. Astronomy for Beginners - The Planetary Society

    Here are a few tips to get you started with astronomy for beginners, and some ways to deepen your connection to the cosmos. Some locations are better than others for stargazing, but you can still do it …

  10. Introduction to Astronomy | Department of Astronomy | Illinois

    Introduces the student to the basic concepts of modern astronomy.