Robert L Zimmerman

ASTR 123, Assignment #5

Properties of Galaxies, Chapter 25

Assigned Nov 3, 2009----Due Nov 10

 

   Answer the questions and return images from the Web. Place all images in a word processor.

                                                              Questions

 

1. The description of a head-tail galaxy is given in section 25.1. Explain the shape of the radio source and what it reveals bout the galaxy and the intergalactic medium.

2. Draw figure 25.17 which relates the size of the galactic bulge with the mass of the supermassive blackhole. Explain the results.

3. Figure 25.20 describes the sequence of Galaxy Evolution and AGNs. Briefly explain the figure. What is the final type of galaxy created by a major merger and a minor merger?

4. Sketch the picture of the Lyman-Alpha forest found in Fig 25.25 (page 701). You donŐt have to include the details only the idea of the sketch. Describe the diagram and explain what creates the forest and why are the peaks redshifted?  

 

                                          Images

 5.  Return the computer realization of the distribution of the Lyman-alpha hydrogen clouds. Include a brief description.  

http://antwrp.gsfc.nasa.gov/apod/ap030126.html

6. Light from some quasars is pulled around a massive galaxy in different paths, making multiple images of the same quasar. The amount of bending is used to determine the mass of the lensing galaxy. Return an image of a quasar whose light has been bent by a gravitational lens. Include a brief description. 

 http://antwrp.gsfc.nasa.gov/apod/ap990331.html

7. Return an image of a dark matter map around the bullet cluster of galaxies. Include a description about how the dark matter map was made.

http://antwrp.gsfc.nasa.gov/apod/ap060824.html