The objective of this laboratory exercise is to take CCD images of a total of 4 objects from the lists below:

List #1: No more than one object can come from this list: Mercury, Venus, Mars, Saturn, Jupiter, Uranus, Neptune. For a current listing of their positions, see http://www.heavens-above.com .

List #2: Three or Four of the objects will come from the list below. Clearly, not all objects are visible at the same time or even on the same night. Check the LST and then look at both the object’s RA and Dec. Some of the objects below are real easy to find, others will only be visible with the CCD. For the latter, you will definitely want to center the telescope and reset the encoders on a nearby, fairly bright star; then you can move the telescope a few degrees to the object’s position and take an image. If everything has worked right, the object should be in the image; if not, then use the slow motion controls to move the telescope a few arcminutes N, S, E, or W and try again…

If this doesn’t work, you may have to pick another star that is closer to the object and reset the encoders after centering the new star. Galaxies are often the most difficult objects to find because of their low surface brightness. Note that many of the objects below are Messier objects (i.e., those with the M followed by a number designation). A good introduction to them (and some very pretty pictures) is at http://www.seds.org/messie

Preparation

Remember, objects not up at 9 or 10PM may come up later in the night. Conversely, they may set early so you will have to start to locate them in the twilight. Remember, the telescope will not point below 15 degrees altitude and will not point close to the pole (>65degrees )

You might be able to find what is up from SKY Online (http://www.skypub.com), from the makers of Sky and Telescope magazine.

Make your list for the night and note which times you can see your objects.

Observations

1. center the object in the finder then in the wide field eyepiece
2. to take the picture offset the telescope 3'7" (187") south [this moves the object about 60% to the top of the wide field view but centers it on the CCD.]
3. flip the mirror to CCD
4. take the picture
5. if the image is not very sharp, focus and take another exposure
6. repeat step 5 until the image looks decent
7. save the picture with a descriptive name

Make sure you save the CCD file in your subdirectory and fill out the CCD form for each picture.

You may try different exposure times and different colors. Each object will respond differently.

Write-up

Pick your best pictures. Start with a short narrative about which nights you observed and the quality of the night. On each picture, or on a separate list, give a short description. For example,

The Orion nebula in Infrared; 60 sec exposure; This was not sharp as our exposure in Blue

If you have done any special reduction such as combining several colors give a short narrative how you did it.
Conclude with any general observations, including what you did right and what you did wrong. Add any general reflections

E-mail a text file with your descriptions to me. Do not attach the images but refer to their names in your write-up.

Keep all your images in your folder on the CCD computer so that I may inspect them and see what you did. Don’t worry if some of the images aren’t perfect. But I do expect to see some attempt at focusing the CCD.