Creating Finder Charts

Web resources

I. Sky View

1. Go to : http://skyview.gsfc.nasa.gov/
2. Under "Interfaces ?" choose "Basic".



3. In the "Required Parameters" space type in the coordinates of your asteroid.

4. In the "Survey(s)" list look for and select "Digitized Sky Survey".
5. The most important "Optional Setting" will probably be the "Image Size". The default size is 300 times the intrinsic pixel size of an image. For one test area this resulted in a field-of-view of about 8.5 arcminutes by 8.5 arcminutes. Accept the default value and adjust it as necessary on the next request.
6. Just above the "Required Parameters" space click on the "Submit" button and your sky image will appear shortly.
7. This image is in GIF format and can be saved to your computer or printed out. There is also a choice for 32-bit FITS images. Download these only if you have software which can handle 32-bit images. The FITS format provides more flexibility for image processing and field comparison.
This image should be helpful in locating the star field containing your target.
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II. Lowell Observatory provides a service for generating a plot of the stars in the field-of-view (FOV).

1. Go to : http://asteroid.lowell.edu/ and under "Observational Aids" select ASTPLOT.
2. Choose an observatory closest to you or if you are observing from North America, you can accept the default value of Lowell Observatory-LONEOS. Code for Yerkes Observatory is 754.
3. Type in the Universal Time date and time at which you wish to observe.
4. Type in the right ascension (RA) and declination (DEC) of your target.
5. Accept default Limiting Magnitude and Minimum Probability choices.
6. Type in your FOV (field-of-view) values in arcseconds. (1 arcminute = 60 arcseconds)
7. Accept the default plot options.
8. Click on "Build Plot" and a plot will appear shortly of your piece of the sky.

This plot is in jpeg format. You can save it or print it out and use it for field recognition to zero in on the location of your chosen asteroid. 
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Non-Web resources for creating charts

I. The RealSky CD set - a remarkably useful resource !

This is the Palomar Observatory Sky Survey on 9 CD ROMs. "The RealSky CD provides single-color (one passband) images of the entire northern sky, down to -15 degrees, the approximate location of Sirius, digitally compressed by a factor of 100x. For Windows, Macintosh O/S, Unix and VMS."

The Southern Sky is also available. These sets provides extremely realistic sky images.

Both are available from the Astronomical Society of the Pacific for $250 (USD).
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