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1: Introduction to Astronomy

Last updated

Jul 23, 2025
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- Licensing
- 1.1: Module Introduction

Lumen Learning
Lumen Learning

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Learning Objectives

Upon completion of this module, the student will be able to:

Describe the characteristics of the major classes of objects in the Universe
Recognize the scale of the Cosmos, using Astronomical Units and Light travel
Identify specific Constellations
Describe the characteristics of specific Constellations
Identify specific Asterisms
Differentiate between Constellations and Asterisms

This module starts with the question, “What is Astronomy? ” Simply stated, Astronomy is the study of the Universe. Astronomers classify objects into various groups based on characteristics and locations in our Universe. Some of these classifications, such as stars, are easy to understand scientifically. Other objects are more difficult to classify, and in some instances, to entirely understand. This module identifies basic objects in our Solar System and those beyond, the overall scale of the Universe, and patterns in the night sky. So welcome to your Universe: a beautiful and incredible place, as you will soon learn.

1.1: Module Introduction
This page discusses astronomy, highlighting its historical evolution from storytelling to modern discoveries facilitated by space exploration since 1957. It emphasizes the significance of learning about celestial object classifications, the Universe's scale, and night sky patterns, with an educational module designed to foster appreciation for the cosmos.
1.2: Basic Objects in the Universe
This page explores Astronomy as the study of the Universe, detailing celestial objects like stars, planets, dwarf planets, satellites, asteroids, and comets. It explains that stars are gas spheres in nuclear fusion, planets orbit stars, and dwarf planets do not clear their orbits. The Solar System consists of the Sun and orbiting bodies, while larger structures include stellar systems, galaxies, and superclusters, with the Universe encompassing all matter and energy.
1.3: Scale of the Cosmos
This page explains the vast distances in the Universe, emphasizing the challenges of understanding these scales. It notes the Earth-Moon distance at 230,000 miles and the Earth-Sun distance at 93 million miles, using the Astronomical Unit (AU) for simplification. Jupiter's diameter is about 88,000 miles, while the Sun’s is approximately 850,000 miles.
1.4: The Constellations
This page discusses the creation of constellations by early cultures based on star patterns, with 88 officially recognized today, mainly from Western European traditions. While some are identifiable, most require equatorial viewing. Different civilizations interpret constellations uniquely, for instance, Orion is viewed as a warrior in China, Osiris in Egypt, and a general in Hindu mythology.
1.5: Other Patterns
This page discusses asterisms, which are star patterns within constellations but not official ones, offering examples like the Big Dipper and Pleiades. It notes their various cultural names and includes a quote by Ralph Waldo Emerson that highlights humanity's enduring fascination with stars despite modern distractions.

Learning Objectives

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