Campaign Goals: September 26 - October 1, 2000
The goal of this campaign is to obtain scientifically useful observations of comet 9P/Tempel 1 over several days. During this campaign, the morning sky will be dark since new moon occurs on September 26. The comet is visible from the southern and northern hemispheres and has a predicted apparent visual magnitude of about 17.0.
Again, we are requesting photometric V- and R-filtered images of Tempel 1. We can measure photometric magnitudes from these images with respect to heliocentric distance. Also, R-filtered images tell us about the dust environment, which is critical to the design of the Deep Impact spacecraft. If you cannot take V and R images, take unfiltered images.
If you have not yet produced a set of standard star images using your photometric filters, please attempt a set if you have a photometric night. Instructions follow.
If you cannot take V and R images, take unfiltered images.
If you attempt to image the comet and it is too faint to record, please send us an email describing your attempt AND THE LIMITING MAGNITUDE for your observing run! This information can be useful!
Questions? How to Contact Us!
Please send questions about this campaign to Stef McLaughlin, University of Maryland.
During the campaign weekend, Stef will monitor the observers' message board. Also, if you have an urgent question, you may leave a message at 301.405.3605 (USA).
Summary of Observing Procedures: August 5 - 6, 2000
In general, we need you to:
- Make images of the comet using the following filters:
- Photometric V and R filters. If your filter system has an infrared-cutoff filter, it must be removed before you observer the comet (or take flats) with the V and R filters.
- Photographic R and G filters from an RGB set. You may try the B filter, but comets do not emit much in this band. If you use photographic R and G filters, you must include an infrared-cutoff filter.
- Clear (or no filter). We will use these images to monitor overall brightness changes over time and heliocentric distance.
- We will use V- and G-filtered images for photometry and R-filtered images for photometry, coma structure, and dust activity studies.
- We suggest a total exposure time of 4+ minutes. To accomplish this, you can take multiple, short exposures of 1-3 minutes (with accurate tracking) or you can make single, long exposures of 4+ minutes (with accurate tracking) so that a magnitude of ~19.5 is reached. If the comet trails a little, we can still perform brightness analysis.
- If you have a photometric night, take calibration frames of several standard stars at different air masses. A list of standard stars and instructions for taking calibration frames are at: Standard Stars.
We need your calibration frames so that we can perform accurate photometry of the comet as part of our brightness analysis. If your comet images contain a few non-standard stars we can perform some brightness analysis but it will less accurate and less scientifically useful!
If you cannot take calibration frames during this campaign, we will ask you to take them in the near future, when you have the time and a photographic night.
- When taking standard star images, please note the star's identification or designation in your observing log.
- Take dark frames.
- If you have a nitrogen-cooled CCD, make 5-10 bias frames and 3-5 dark frames using an exposure time of 1-2 minutes.
- If you have a thermoelectrically-cooled CCD (most commercial CCDs):
- If your CCD software performs automatic dark frame subtraction, turn this feature on. Indicate this in your observing log and send us your dark-subtracted comet images and flat fields.
- If your CCD software does not perform automatic dark frame subtraction, make 3-5 dark frames using the same exposure times used for the comet images. These dark frames should be taken immediately before or after comet images.
- Make 3-5 flat frames for each of the filters you observe with. Do not saturate the flat frames. Shorten the exposure time so that pixel values are about 20% of your CCD's maximum pixel value.
- If your CCD software performs automatic dark frame subtraction, turn this feature on. Indicate this in your observing log and send us your dark-subtracted flat fields.
- If your CCD software does not perform automatic dark frame subtraction, make 3-5 dark frames using the same exposure times used for the flat fields. These dark frames should be taken immediately before or after flat fields.
- Keep an observing log. Include information about weather conditions, seeing, moon, temperature, and humidity. Please send your log to us by email or by FTP. Text, MS Word, and RTF files are acceptable. For an example of an observing log, go to: Observing Logs.
- Format all images as FITS.
- Transfer unprocessed FITS images to Stef McLaughlin using an anonymous FTP process. You may also send us any images you process, but we also need your raw, unprocessed images. Please FTP your observing log.
STSP Coordinator: Stef McLaughlin
Webmaster: Elizabeth Warner
Last Updated: Wednesday August 29, 2007