{[ promptMessage ]}

Bookmark it

{[ promptMessage ]}

homework7 - Astronomy 362 Problem Set#6 Due Friday March 7...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Astronomy 362 Problem Set #6 Due Friday, March 7 at 12 noon In the homework problems below, “C&O” refers to your textbook. I have selected the problems with the expectation that they will take up to 1 hour of hard thinking/calculating each. If you are taking longer than this, feel free to come by my office to hash out where you are stuck. Note on collaborating: You may work together on this problem set, but all work presented here must be your own. You must clearly acknowledge any people you collaborated with. ASSUMED READING: Please finish C&O Chapter 25 (Sections 3 and 4) for homework (if you haven’t already). 1. Explain (in words) how the virial theorem for gravitational systems 2 K + U = 0 allows you to use the redshift-measured velocities for galaxies in a galaxy cluster to determine the mass of the galaxy cluster. I am not asking you to actually do any derivations of an expression for the mass, rather, I want you to explain how you obtain K and U and how they are related to velocities and the masses. 2. [C&O 25.11 (tweaked)] Let’s consider the evidence for a supermassive black hole at the center of our neighbor, the Andromeda galaxy (aka M31). a. From the data shown i n F i g u r e 2 5 . 3 7 (reproduced here) for the stellar rotational velocities near the c e n t e r o f M 3 1 , estimate the amount of mass within 1” of the center of the g a l a x y ( i n s o l a r masses). Compare your answer with the value quoted in the Figure 25.37 The stellar velocity dispersion and rotational velocities of stars near the center of M31. measured along
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
Image of page 2
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}