Ch 27: The Sun's Structure & Components

About This Chapter

Watch online video lessons to learn about the sun's layers, nuclear fusion, gravitational contraction and more. Each lesson includes a helpful self-assessment quiz that can tell you instantly how well you understood the presentation.

The Sun and Energy - Chapter Summary and Learning Objectives

Use this chapter to study the sun's life cycle, from its origins as a cloud of gas and dust to the phases of gravitational contraction. Our instructors can show you how the energy generated from this process created enough heat for nuclear fusion to occur. You can also take a closer look at the structure of the sun and learn how its sunspot cycle affects Earth. Lessons in this chapter are designed to teach you about the following:

  • Gravitational contraction
  • The life cycle of the sun
  • Sun structure
  • Steps in nuclear fusion
  • The ideal gas law

Video Objectives
Structure of the Sun Explore the radiative and convective zones in the sun's inner layers. Study the temperature of its outer layers.
The Sun's Atmosphere Identify characteristics of the sun's chromosphere and corona.
Stages of the Sun's Life Cycle Learn how nuclear fusion transformed the sun from a nebula into a main sequence star. Chart the sun's eventual development into a red giant and white dwarf.
Sunspots & the Magnetic Cycle Discover the length of the sunspot cycle. Learn how it affects our climate.
Nuclear Fusion & the Sun Differentiate nuclear fission from nuclear fusion. Explore steps in the proton-proton chain reaction.
Generating Energy Through Gravitational Contraction Relate gravitational contraction to the sun's history.
The Ideal Gas Law and the Gas Constant Explain the connection between variables represented in the ideal gas equation.
Using the Ideal Gas Law: Calculate Pressure, Volume, Temperature or Quantity of a Gas Practice using the ideal gas equation to solve for unknown variables, such as pressure, volume, moles or temperature.

12 Lessons in Chapter 27: The Sun's Structure & Components
Test your knowledge with a 30-question chapter practice test
Structure of the Sun

1. Structure of the Sun

Discover the layers of the sun, including the core, radiative zone, convective zone, photosphere, chromosphere, and corona. Find out which layers you can see from Earth. Investigate what sunspots and solar flares are.

The Sun: Atmosphere & Facts

2. The Sun: Atmosphere & Facts

This lesson will go over what the three layers of our sun's atmosphere are, the sun's surface temperature, chemical composition, radius, and distance from Earth.

Photosphere: Definition & Features

3. Photosphere: Definition & Features

This lesson will go over the sun's photosphere (its visible 'surface'), including where light comes from, how hot it is, and what granules and supergranules are.

Chromosphere: Definition & Properties

4. Chromosphere: Definition & Properties

This lesson will explore some of the interesting features of the second layer of the sun's atmosphere, the chromosphere, including spicules and its pinkish hue.

The Solar Corona & Solar Wind

5. The Solar Corona & Solar Wind

This lesson will define the solar corona and go over how it's involved with the formation of the solar wind and why it's hotter than the photosphere despite being the outermost layer of the sun's atmosphere.

Solar Flares, Solar Prominences & Coronal Mass Ejections

6. Solar Flares, Solar Prominences & Coronal Mass Ejections

This lesson will go over three events caused by magnetic interactions in our Sun. They are prominences, flares, and coronal mass ejections. We'll also touch base on how the latter two can affect life on Earth.

Helioseismology & the Heliosphere

7. Helioseismology & the Heliosphere

This lesson will go over important terms beginning with helio-: heliosphere, heliopause, and helioseismology - what they are and what importance helioseismology plays in our understanding of the sun.

What Are Sunspots?

8. What Are Sunspots?

This lesson will describe for you what sunspots are, where they appear, what parts they have, and why they're dark. It also discusses what differential rotation and a sunspot cycle are.

Why Do Sunspots Occur?

9. Why Do Sunspots Occur?

This lesson will outline for you why sunspots occur in its photosphere as we go over the Zeeman effect, polarity, and how the sunspot cycle and solar cycle are linked.

The Babcock Model of the Sun's Magnetic Cycle

10. The Babcock Model of the Sun's Magnetic Cycle

This lesson will cover a model called the Babcock model or Magnetic-Dynamo model, which helps to explain how many of the features of the solar and sunspot cycle occur.

Stages of the Sun's Life Cycle

11. Stages of the Sun's Life Cycle

Discover our sun, the provider of energy for life on Earth. Learn how the sun was born, how it lives as a main sequence star, how it will age into a red giant and how it will die as a white dwarf.

How Energy Moves Within the Sun

12. How Energy Moves Within the Sun

This lesson will describe how energy is carried from the inner reaches of the Sun, through the radiative zone, then the convective zone, and finally into space.

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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