Objectives: The Milky Way
Chapter Objectives:
The Universe is composed of billions of separate collections of stars known as
galaxies, and our home galaxy is an example of the spiral type of galaxy. Our
Sun is located in the outer reaches of the Milky Way Galaxy and is one of the
several hundred billion stars that comprise this typical spiral. In this
chapter we will study the parts of the Milky Way Galaxy: the halo, the disk,
and the central bulge. The views of our galaxy in different wavelengths will
be illustrated and the resulting evolution of our perception of our home
galaxy will be discussed. The spiral structure found in the disk
portion of our galaxy will be described and the mechanisms that may have
caused this spiral pattern will be explored. The concept of dark matter and
its role in the dynamics of our galaxy will be introduced.
Chapter Skills:
After studying this chapter you should be able to
- Sketch the Milky Way galaxy in an edge-on and overhead view and indicate our Sun's postition.
- Discuss how our perceptions concerning our galaxy (and our place in it) have changed through the centuries.
- Describe the three basic components of the visible matter of the Milky Way galaxy.
- Give the evidence that indicates there is a dark matter halo surrounding our galaxy.
- List the evidence that suggests our galaxy is a spiral type galaxy.
- Describe the density wave explanation for spiral arms.
- Show how self sustaining star formation could also lead to a spiral arm pattern.
- Discuss the components of the interstellar medium within the Milky Way.