Observing Proposal Format

last revised 6/2/17

Observing Proposal Format

Observing time on a telescope is a precious resource. In most cases, telescopes are oversubscribed, i.e., requests add up to more hours of observing time in a scheduling period than are available. For example, the Hubble Space Telescope is typically oversubscribed by a factor of five; the Keck telescopes, by about three. So how is it decided who gets time? Astronomers are required to submit an observing proposal that will be evaluated by a panel of experienced users. The more highly rated a proposal, the more likely it is that time will be granted.

Proposals should be written formally and should include the following sections:

    • Scientific Objective: What is the scientific purpose of the project? What will it prove, demonstrate, convey, or elucidate and why is this interesting and worth doing? If you are successful, what will you have accomplished?
    • Target Object(s): What will you observe? Give the name (common name and/or catalog designation); celestial coordinates (RA and Dec); Galactic coordinates, if relevant; angular size, some measure of brightness (apparent magnitude for stars, surface brightness for nebulae/galaxies, etc.); and anything else about the target that has a bearing on the actual observations, e.g., if your object is variable, and you want to observe at maximum, or at minimum, say so.
    • Observing Time: Clear weather will determine the days you can observe. When will your target(s) be visible? What time(s) of night would you like to observe? The answer should include not just calendar dates, but time of night, moon phase restrictions, if any, and why this is (or isn’t relevant). A planetarium program like Starry Night (available on the Department Macs) can help you to determine when an object is highest in the sky (i.e., near meridian transit), and thus is best placed to observe. How many hours of telescope time do you anticipate your observing will require? Remember, it is in your interest to be as flexible as possible!
    • What equipment would you like to use? List telescope, detector, and other applicable equipment like filters, and gratings.
    • Procedure: A paragraph or two should demonstrate that you have thought about what you will do when you are actually at the telescope. How long will your exposures be? How many will you take? What calibration frames will you need and how will you use them to calibrate your data?
    • Data Reduction Plan: Though you won’t necessarily know in advance exactly how you will calibrate/reduce your data, you should have some idea of the process and the tools you might use. If you plan to consult with Dr. Souza along the way, say so.