Planning Observations Lab

Introduction

The purpose of this exercise is to prepare a visual observing plan that will be carried out during mid October at the UF Rosemary Hill Observatory (RHO). In addition, you should prepare a similar hypothetical plan to be carried out at the Mount John University Observatory, Lake Tekapo, New Zealand in mid December. Specific dates will be assigned when we meet in the lab. The telescope to be used at Rosemary Hill Observatory will be the 46 cm. aperture reflector. The telescope to be used at Mount John is about 65 cm. in aperture. You can use reference materials located on the web in developing these plans.

Observatory/Night Information

The first thing to do in planning an observing program is to calculate or look up the basic information about the night (or nights) involved. You will want to know

a) Sunset, Astronomical Dusk, Astronomical Dawn, Sunrise

b) Sidereal Time at Midnight

c) Moonrise, Moonset, moon phase

d) rising, transit, and setting times for your selected objects as appropriate.

The latitude and longitude of most of the world’s observatories including the UF’s Rosemary Hill Observatory (Bronson Florida) are listed in any recent Astronomical Almanac or American Ephemeris and Nautical Almanac. Many observatories publish tables of sunset etc., otherwise you will have to calculate these values using tables in the Almanac or Handbook or a web resource.

Selection of Objects

Using the various resources available to you; put together a list of 6 to 8 objects for each observing site. The objects should be selected from the following categories.

1) Two or three “bright” stars (stars you can -in principle- identify with the naked eye) to use as “focus” and/or “sync” stars.

2) One or two solar system objects

3) Two or three galactic (in the Milky Way galaxy) and/or extra-galactic objects

Keep in mind when you will be observing and that clouds may interfere with some parts of the sky. In addition, recall that skies may not clear until later in the evening. Many observers pick one or more objects that are high at the start of the night, more high at midnight, and still more that are high at the end of the night. Since you may not want to stay up all night, you may want to compress this time schedule for the RHO plan (since you may well get the chance to actually observe these objects).

Lists of interesting objects can be found in the “Observers Handbook”, “The Astronomical Almanac” and many other publications. In addition, many lists of objects (and images of them) can be found on the web.

Finding Charts

For any objects that are not “naked eye” or easily identifiable in the telescope, you will want to prepare finding chars. Typically, such a chart will show about 15 arc-minutes of sky centered on your object. Various computer programs may be useful for preparing finding charts. Several may be available on the lab computers including “The Sky for Windows”. In addition, you may want to use a web site to get a finding chart. It is important that label your finding chart show N/S/E/W and the scale used.

Planning the Night

The night plan is the primary end result of this exercise. It is a list of objects in the order that they will be observed. Additional comments or indications of contingency plans for bad weather or poor observing conditions should be part of the observing plan.

One nice way of presenting a night plan is in the form of a chart of the night as shown below (R=rise, T=transit, S=set): Note that for an observing period spread over several weeks, it might be necessary to have several versions of the plan.

	EST/EDT
OBJECT		18	19	20	21	22	23	0	1	2	3	4	5
Twilight		------	------	---x								x-	-------
M42		R<		T	------	------	------	S
Moon					R--	------	------	---T--	------	------	----S
Saturn					R				T
M31			R				T				S

The Write-up

The initial work of this exercise should be carried out in your lab notebook. However, you should then write out the results in the form of an observing request to the appropriate TAC (Telescope Allocation Committee). In addition to listing the objects to be observed, the request should show the observing plan including the sequence of observations and any provisions for weather problems etc. The purpose of a telescope time request is to persuade the TAC that your research is important, that your project is appropriate to the telescope(s) involved, and that you have planned the program so as to make efficient use of valuable telescope time. Be sure to mention why it might be interesting to observe the objects you have selected or what useful purpose might be served by such observations. Finding charts would not normally be part of a telescope time request but should be included in this case.

This write-up is due two weeks from the lab exercise date given in the syllabus.

Night planning Work sheet (make copies if you want)

OBJECT	17	18	19	20	21	22	23	0	1	2	3	4	5	6
Twilight

OBJECT	17	18	19	20	21	22	23	0	1	2	3	4	5	6
Twilight