Assignment #4 Properties of Stars

ASTR 122, Robert L Zimmerman

Assigned Monday Feb4 due Monday Feb 11, 2008

You are asked to return various images and answer a few questions. You MUST place all images in a word processor and include a description of the images with its URL. You do not have to use the suggested URLs that I give you.

Questions

1. Consider the P-P process that is described in the notes and in chapter 16. Write the equations for steps in I, II, and III. Below each equation describe what Isotopes are colliding and what is being produced. How much hydrogen must be converted into helium every second to produce the Sun’s energy? How many tons of energy are produced every second? (Ref Move Precisely 16-2)

2. What is neutrino oscillation and how does it explain the missing neutrinos from the sun? What are the names for the three neutrinos?

3. From appendix 3 in the back of your book you can find information about the stars. Complete the following table

Consider the stars:

Star          Spectral Class, (Visual)  Lum,   Abs Mag,   App Mag,

Sun                   G2V            1                    4.83               -26.74

Rigel (A) ,

Betelgeuse,

Sirius (A),

Aldebaran,(A)

From this information answer the following questions: Which star is the hottest?   Which star has the greatest Luminosity? Which stars appears the dimmest to the naked eye?

Images

4. Return a picture of the Orion constellation that has names of its brightest stars and a diagram of the constellation http://www.slivoski.com/astronomy

Also return a picture of M42. Include a several sentence description of the Nebula. What is the name of the young open cluster of stars that lights the center of the nebula? Possible URLs are

http://www.seds.org/messier/m/m042.html

http://antwrp.gsfc.nasa.gov/apod/ap040713.html

http://antwrp.gsfc.nasa.gov/apod/ap040325.html

5. The bright red star in the shoulder of Orion is Betelgeuse (Alpha Orionis). It is a Red Supergiant about 10 times more massive than the Sun. Betelgeuse is over 1000 times larger than our Sun. If it were placed at the center of our Solar System, it would extend past the orbit of Jupiter. Betelgeuse brightness changes due to its rhythmic change in size over an approximate six-year cycle. Return one image of the Red Giant with a brief description of its properties. Include the URL under the picture. Possible URLs are

http://antwrp.gsfc.nasa.gov/apod/ap990605.html

http://www.alma.nrao.edu/science/betel.html

http://www.nrao.edu/pr/1998/betel/

http://www.nrao.edu/pr/2000/vla20/background/radiostars/

6. Super-Kamiokande is a large, underground; water neutrino detector located in zinc mine in the Japanese Alps. The detector consists of a tank, 40 meters tall by 40 meters in diameter. It is filled with 50,000 metric tons of ultra-pure water.  The detector is lined with 11,200 photomultiplier tubes. These tubes record the light from fast moving charged particles created in or passing through the water. Super-K records about 4000 solar neutrino events per year, approximately 50% of the number expected. The experiment began data taking in April 1996. Return an image of the Kamiokande. Include its URL and a brief description. Possible URLs are

http://antwrp.gsfc.nasa.gov/apod/ap971028.html

http://hep.bu.edu/~superk/about.html

IF THE SKY IS CLEAR

7. Go out at about 9: 00 PM or later and find Orion, Betelgeuse and M42 (Orion Nebula). Find Sirius in Canis Major and state where it is relative to Orion (left or right of Orion). Find Aldebaran in Taurus and state where it is relative to Orion (left or right of Orion). Mark the time and date you made your observation. For a reference of where these objects are check the star chart S-3 in the back of your book.