Making Star Maps

In order to specify the position of any object in the sky, we normally give its CELESTIAL COORDINATES. An EPHEMERIS for an object in the sky is a listing of celestial coordinates that pinpoints the object's location as it moves in the sky. The first step in finding out where comet Hale-Bopp will be at any given time is to find its ephemeris--here's what to do:

1. Direct your web browser to the Hale Bopp Ephemeris or the URL http://newproducts.jpl.nasa.gov/comet/ where you will find the Ephemeris for Hale-Bopp.
2. Download the ephemeris and either store it on your computer, or print it out on paper.

Once you have the ephemeris--the series of coordinates for the comet--you can plot the path of the comet on these star maps:

• Star Map for Fall, 1996 (with celestial coordinates)
• Star Map for Winter, 1997 (with celestial coordinates)
• Star Map for Spring, 1997 (with celestial coordinates)

Take the star map you make and try to find a dark sky location for your search in the real sky.

Happy comet-hunting!!!