Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.

Planning an Observing Run

So, you have a list of targets in mind. Before you head out to the telescope, you need to check over the list to find out which ones are suitable for your circumstances. Important factors are:

(*) Just what counts as a decent altitude, anyway? In general, if you have the option, pick times when the airmass of your object is less than 1.5, or at most less than 2. Otherwise, your object will be blurry and faint, and your hard work may not gain you good results.

It helps to know the parameters of your instrumental system. You should know, or be able to find out, all of the following:

One tool that can help with some of this work is

There are actually several of these scattered around the WWW; some are maintained by large observatories and are specialized for use with a particular telescope or instrument.

After you have checked and double-checked your list to pick out the best objects, you should make up a finding chart for each one. On the finding chart, be sure to include such information as the name, coordinates, rough times of rise and set (for the current time of year). Indicate clearly the object(s) of interest in each field. Your chart should show the size of the field, in arcminutes, and also note the orientation: North this way, East that way.

Making an observing proposal

Large observatories have more users than telescopes (alas). In order to prevent fistfights from breaking out inside the domes, observatories create Time Allocation Committees (TACs) to divvy up telescope time to the various astronomers. The TACs base their decisions on observing proposals, which describe

You can find examples of some observing proposals on-line:

You must create an observing proposal for this class and submit it by Thursday, Apr 13. The TAC will meet on soon thereafter to consider each proposal.

The pieces of an observing proposal

Your proposal must answer the following questions:

Who? Personnel
Who are you? What is your experience?

What and Where? Target(s)
What will you look at? What sort of thing is it? How bright is it? Make a table showing the position and magnitude of each target. Include a finding chart for each object, with the target clearly indicated.

How? Equipment
What telescope will you use? Which camera? Will you use filters? If so, which ones? What exposure times are required?

When? Times and Dates
When is the target visible? What are the earliest and lates dates within the period under consideration which satisfy your needs? Are there particular dates on which special events occur? Which moon phases are acceptable, and what constraints does that place on the dates and times?

Why? Scientific Justification
What's the point? What do you plan to learn from these observations? Explain how the images you will acquire supply the information you want to know. You should include references to other work on this or similar objects -- you might do literature searches on You should describe the type of reductions you will perform on the images: astrometry, photometry, or something else. You should also explain any additional analysis; for example, if you are looking for variability, you should explain how you will use the light curve to determine the period and amplitude of variation.

You must be able to show that the time and equipment requested will yield images that can answer your scientific questions.

When you are ready, you can fill out the observing proposal form.

Last modified 4/13/2010 by MWR.

Creative Commons License Copyright © Michael Richmond. This work is licensed under a Creative Commons License.