This laboratory requires your laptop. If you want to work in pairs, that is fine. Please, however, no more than two people to a group.

We will be following one of the Contemporary Laboratory Exercises in Astronomy (CLEA) produced in the Physics Department at Gettysburg College. You will use a telescope and spectrophotometer simulation to measure the brightness and color of a number of stars in the Pleiades cluster. From this data, you will create an HR diagram, and use this diagram to determine the distance to the cluster.

Dowload the Student Manual. You can hand in your student manual, which contains worksheets, or you can hand in your own paper instead. You will want to make a plot, so either be prepared for that with your computer or have graph paper on hand. I will have the "plastic sheets" which are useful for the distance determination part of the exercise.

Download and install the program on your laptop. Start up the program, open the dome, turn the tracking on, and get used to moving the field of view around. Start on page 9, taking your "sky" readings for background subtraction, and go through the rest of the exercise. When identifying stars, they will not all be very close to the listed coordinates in the table on page 14. You may want to keep your own table of coordinates instead.

You do not need to measure the U magnitude for all the stars, however after you've made your HR diagram, find a star that is close to the A0 spectral type, and see if U-B=B-V=0, approximately.

If you are running out of time, it is more important that you plot up just some of the stars, and use the result to calculate the distance. However, be sure to get some dim stars on the plot, and pick out the oddball stars discussed on page 10.