Observational Optical Astronomy

Course Description:

This is a one unit course which lasts the entire academic year, i.e., you must register for both semesters to get credit for the course. The course consists of a series of hands-on observational projects. These projects are centered around several which require use of the CCD camera on the 16 inch Schmidt-Cassegrain telescope located in the large dome of the Strawbridge Observatory. Data from these observations will be analyzed with either the software package IRAF or the IDL programming language. You may use the workstation located in the computer room of the Observatory for this analysis, or any other workstation with the necessary software to which you have access. [To access the observatory after hours, you will need an Ob3 key. For those of you who do not already possess this key, obtain a key request form from the instructor and take it to Security as soon as possible.]

The course will be informal. After the initial instructional observing sessions, each observing team (consisting of two or three students) will have the responsibility for scheduling observations. The regularly scheduled “class time” (M 7:30-10:00 p.m.) will serve three purposes. For the first few weeks of the fall semester, this time will be used for workshops on a variety of topics; e.g., an introduction to CCD cameras, an introduction to the IRAF software package, operating the 16” Schmidt-Cassegrain telescope, analyzing astronomical data, etc. During the Spring semester, we will meet every other Monday during this time for additional lectures, and to discuss the details of individual projects and reports. Finally, this time slot will give assurance that there is at least one night a week when members of the observing teams do not have scheduling conflicts (in the past, scheduling has been a big problem).


There is no textbook for the course; however, the book Handbook of CCD Astronomy by Steve Howell will be placed on reserve and occasionally readings from it will be assigned. CCDs (Charged Coupled Devices) have arguably revolutionized observational astronomy and understanding how they work is essential for a course on this topic.


The primary prerequisite for this course is Astro 205; therefore, it is expected that all students will have a working familiarity with the 12" Schmidt-Cassegrain telescope located in the small dome in the Strawbridge Observatory. It is anticipated that some students will also have some familiarity with the Linux computer operating system, the IRAF software package, and/or general CCD camera operation. However, students unfamiliar with these systems will be quickly brought up to speed and will then be able to direct most of their efforts to the observing projects. The primary purpose of the first two projects is to learn CCD camera operations and basic photometric techniques.

Schmidt-Cassegrain is a fairly complicated and delicate instrument, and it is quite susceptible to damage from misuse. It is imperative that you be thoroughly checked out by your instructor before using the telescope. Two trained observers must be present during any observing run.

Learning Goals:

(1) particular astronomical phenomena firsthand through observing specific objects and analyzing the data with the toolds of the research astronomer.;
(2) how to use perhaps the most versatile instrument of the modern astronomer, the CCD camera;
(3) the operation of telescopes, e.g. tracking, guiding, pointing errors, seeing, balancing, etc.;
(4) planning observing runs, e.g. how to anticipate good weather patterns, how to determine which observations need dark time and which can get by with bright time, etc.;
(5) the details of modern astronomical data processing, including the IRAF package and/or IDL software and such procedures as flatfielding, scattered light correction, aperture photometry, surface photometry, spectral analysis, etc.
(6) the fine art of scientific collaboration—students will work in teams of two or three and will be required to change partners during the year.


The following three projects are required for the completion of this class:
1. An Introduction to CCD Observations: Characterizing the CCD Camera.
2. BVRI Photometry of a Mystery Star near M32.
3. Color Magnitude Diagram of an Open Star Cluster.

There may be one or two additional projects. The following is a list of some possibilities; however, each observing team can create projects of their own:

4. Surface photometry of the nuclear jet in the giant elliptical galaxy M87 (using adaptive optics).
5. Imaging a globular cluster (using adaptive optics).
6. Measuring the spectra of different stellar types.
7. Measuring the spectra and redshift of a distant galaxy.
8. A high-resolution spectrum of the Sun (using the solar ceolstat telescope)

Formal Reports:

Formal reports will be required for at least Project (3) listed above. Work for your reports will include reading about the theory of the astronomical objects being observed. These reports should be written in standard journal style and format. Look at articles in Astrophysical Journal for examples. Reports should include:
(1) a short abstract in which the important results of the observations and subsequent analysis are summarized;
(2) an introduction of approximately one page in which the observations are placed in an astrophysical context. It is in this section that one may wish to review current scientific understanding of the object or the results of previous observations;
(3) an observations section in which the observations are described and perhaps some raw data tables are given;
(4) an analysis section which describes the reduction of the data. This needn't be in great detail. Caution—never put simple arithmetic calculations in this section; just let the reader know how the analysis is being done. Tables, graphs, and images are appropriate in this section. Note—items 3 and 4 are often intermingled;
(5) a discussion and/or conclusions section which gives a clear presentation of the important results and, if appropriate, comments on the significance of them. If you want to wax philosophical, this is the place to do it (in moderation); and (6) a reference section. Use the Ap. J. style. We will discuss these matters in a workshop prior to the first formal report.

Observing Proposals:

In Spring 2010, we will all be writing observing proposals (including me!). We will operate the proposal writing process analagous to the way professional astronomers write observing proposals - starting from the Latex form we will all use and ending with us convening as a Telescope Allocation Committee (TAC) to provide each other constructive comments and rankings on our final, submitted proposals. Details on this project will be forthcoming in lecture.

Helpful links: Instructions for your observing proposals, So you're an observational astronomer handout from the first class, Astronomical magnitude systems and Information about proposing to use NOAO, including exposure time calculators.

Spring 2010 Schedule:

Monday Jan 25 - Meet in observatory at 7:30. Discuss the procedure for obtaining time on telescopes in general, and with respect to specific observing proposals.

Monday Feb 8 - RESCHEDULED: Meet in observatory at 7:30. Topics - Project brainstorm, Signal-to-noise, and other fun.

Friday Feb 12 - Project 1 writeup due

Friday Feb 19 - Submit to me via email a one sentence topic of your observing proposal

Monday Feb 22 - Meet in observatory at 7:30 pm. Topics - Touch base on observing proposals, a brief lecture, plus time to work on proposals.

Friday March 5 - Rough draft of observing proposal. I will provide you feedback by Monday March 15.

Monday March 15 - Meet in observatory at 7:30 to work on proposals and projects.

Monday March 22 - Final draft of observing proposal submitted to me via email in .pdf form. I will electronically circulate the submitted proposals to all members of the class.

Monday March 29 - Meet in observatory at 7:30. Come to class ready to discuss/with your proposal reviews prepared.

Friday April 9 - Project 2 writeup due

Monday April 12 - Meet in observatory at 7:30 to work on projects.

Monday April 26 - Meet in observatory at 7:30 to work on projects.

Friday April 30 - Project 3 writeup due

Final Remarks:

The responsibility for planning and making the observations and analyzing the data is the student's alone. The instructor is only there to give assistance. The student is even responsible (to a degree) for weather conditions. One of the important aspects of being a good astronomer is seeing to it that the appropriate observations are made. If these observations are not given very high priority in your evening affairs, the weather will ultimately beat you. The telescope/CCD/computer system is a complicated one, and problems will invariably arise. In some ways this is a good thing. Research rarely proceeds smoothly. The way in which one solves unexpected problems in large measure determines one's worth as a scientist.