Ch 21: Galaxies, Stars and Solar Systems

About This Chapter

Use the following online video lessons and quizzes to help you understand the Big Bang Theory of how the universe formed. Learn how galaxies, stars, and solar systems were formed and how scientists study them.

Galaxies, Stars and Solar Systems - Chapter Summary and Learning Objectives

In this chapter, our knowledgeable video instructors explain how galaxies form and the different types of galaxies. You'll be introduced to red shift, background radiation, expansion, and other evidence for the Big Bang Theory, as well as how nuclear synthesis formed stars in the early universe. This chapter will discuss expanding and contracting universes and changes in the solar system over time.

You'll learn about the radio, refracting, and reflecting telescopes and how they're used to make observations about galaxies and solar systems. As you progress through the chapter, you'll learn how spiral, elliptical, and irregular galaxies form. When you finish this chapter, you should be able to:

  • Describe the current theory of how the universe formed and the evidence for this theory
  • Differentiate between types of stars by their size, color, and life cycle
  • Understand the structure of the sun
  • Name the stages of the life cycles of the sun, of supernovas, and of supergiant stars
  • Understand both sides of the debate over planets orbiting other stars

Our video lessons include a self-assessment quiz so you can see how well you've learned the lesson as you go. Each lesson also includes a full transcript of the video so you can follow along if you wish. Videos are short and simple to navigate, with tags that let you navigate between the video's main points. In case you get stuck on a key word, key words and phrases are clickable and link to text lessons that clarify these terms.

Chapter Practice Exam
Test your knowledge of this chapter with a 30 question practice chapter exam.
Not Taken
Practice Final Exam
Test your knowledge of the entire course with a 50 question practice final exam.
Not Taken

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