Module 2 – Lesson 4

Lesson 4: Interior Layers of the Sun, Coronal Mass Ejections, and the Solar Wind

Overview

This lesson expands upon the material in Touch the Sun by letting the students view 3-D models of the images they might find confusing about the book’s tactile figures. The processes occurring in the various zones of the Sun and how radiation gets through each layer is emphasized through questions and discussions. The Earth-Sun connection is briefly covered. 

Learning Outcomes

• Given a tactile picture showing the layers of the Sun and/or a Sun ball with the layers cut out and marked, name each layer. 
• Describe what is going on in each layer and how radiation (energy or heat) gets through each layer.
• Distinguish between coronal mass ejections and the solar wind.
• Describe how solar activity changes with time. 
• State how the Earth’s magnetic field protects us.
• Identify an interesting fact about the Sun. 

Materials

• Touch the Sun Braille book by Noreen Grice
• 12-inch or smaller diameter Styrofoam or purchased sun ball with interior layers identified using tactile patterns

Figure 2.4.1. An 8-inch Styrofoam sun carved using a hot Styrofoam cutting tool. This model clearly shows the size of the core and translates the corresponding figure in the Touch the Sun book into 3-D touch access.

Pre-assessment Questions & Discussion

Q. What do you think the sun is made of?
A. Gas (plasma), primarily hydrogen, helium, with tiny bits of other elements.

Q. Describe what the inside of the Sun must be like. What is going on in there?
A. Very hot, fusion, don’t know….

Q. Atmospheric and solar scientists often talk about the “solar wind.” What do you think they mean? A. Some students may know; goal is to introduce the concept of charged particles blowing past the Earth.

Q. There is a saying that states, “When the Sun sneezes, the Earth catches a cold.” What do you think that means?
A. We feel the effect of any change in the Sun, especially when it releases energetic charged particles in the direction of Earth.

Text

Students read pages 11-13, 43-49, and 59-65 of Touch the Sun, broken into logical and time-relevant segments. See follow-up questions for assessing learning and guiding discussions. 

1. The Interior Layers of the Sun: pp. 11-13. Tactile picture on pg. 13 shows convective zone, radiative zone, and core.
   1. List the names of the interior layers of the Sun from the very center to the surface. 
   2. What is going on in each of the layers?
   3. How does the radiation get through each layer?
2. Coronal Mass Ejection and Solar Activity over Time: pp 43 – 49. Tactile picture on pg. 45 shows patterns of coronal mass ejections. Tactile picture on pg. 49 shows changes in solar activity over time. 
   1. 1. What are coronal mass ejections? 
      2. How is the solar wind different from coronal mass ejections?
3. The Sun During a Solar Storm and Space Weather: pp. 59-65. Tactile picture on pg. 61 shows the Sun during an active solar storm. Tactile picture on pg. 65 shows solar wind, coronal mass ejections, and the shape of the magnetic field of the Earth. 

1. 1. 3. What role does the Earth’s magnetic field play in protecting us from harmful effects of the Sun’s activity?

Follow up Questions on the Reading  

Included in the above section.

Reinforcing Activities

Exploration:

Students explore a sun ball that has a wedge cut out or the purchased one and its layers or zones and core marked with tactile patterns similar to those on pg. 13 of Touch the Sun. If there are not enough models for each student, pass the model around to individuals and have them answer the questions related to the core, radiative zone, convection zone, and surface as the model is passed along. As the viewing is occurring, ask the following: 

• Core
  • How does the size of the core compare to the rest of the Sun?
  • Fusion occurs only in the core. Why do you think this is?
  • Why does the core of the Sun have to be so hot, 17,000,000 Kelvin?
• Radiative zone
  • What zone of the Sun lies just outside the core? How does its size compare to that of the core and the layer just above it?
  • What would you have to do to imitate the “random walk” of a photon as it gets through the radiative zone?
• Convective zone
  • What zone lies just above the radiative one? 
  • We can think of this zone as “boiling” like crazy in order to transport heat out to the surface of the Sun. What familiar analogy can you think of?
• Photosphere
  • We call the surface of the Sun the photosphere. Is it really a surface as we would define the term? 

Summary and Post-Assessment Questions

1. 1. Name the various regions of the Sun from the very center to what we call its surface.
   2. What is happening in the core of the Sun? Why is this so important to us?
   3. Are there always sunspots on the Sun? Do their numbers change with time?
   4. Why do we care that the Earth has a magnetic field, even though it is weaker than the Sun’s?

Relevant Information and Links

• From the United Kingdom, a good summary of geomagnetism — https://youtu.be/gRKnDTcv-CE
• The Music of the Magnetosphere (2000)  — http://www.archive.org/details/auroral_chorus_2_cd