 	First, a note to "SolarSys" users:  You will probably want to place "Comets" in the same directory with Mel's "Scope" and my "SolarSys".  The following files are already in that directory.  You do not need to Overwrite files in order to use "Comets".

 	Locale.txt        10/24/2000  12:00pm
 	Nutation.dpt      10/24/2000  12:00pm
 	Sun_J2K.vsp       10/24/2000  12:00pm

-----------------------------------------------------------------------------

 	This program will calculate the position and drift rates of comets.  The results are written into a comet data format (*.cdf) for Mel Bartels' "Scope" program.  The output data file is named "Comet.cdf".

 	The input comet data file used for this program is the same data file set used for Chris Marriott's SkyMap Pro (www.skymap.com).  Chris was gracious enough to allow me to use his comet data file.

 	The program takes Chris' comet orbit elements file "Cmt.txt" and filters outs comets that are not within +/-180 days of its Perihelion passing.  The default is 180 days.  The user can decrease this number to filter out more comets.  This subset is stored in another file named "Cometdat.txt".  The program then computes position and drift rates on this shorten list of comets
 	This filtering process needs only to be run when a new data file is obtained, or sufficient time has passed since the last filtering, or when the user wants to change the filtering range. 
 	Before the program's first execution, it may be a good idea to get the latest comet orbit elements file from the Internet and filter the data.  Cometdat.txt will contain data for Feb 2002 with a range of +/- 180 days.  Directions for obtaining the data file are below.

 	The program when computes the position and drift rates in RA & Dec.  The position is within +/- 5 arc seconds as compare as against SkyMap Pro and the Minor Planet Center ephemeris tables.  This is based on the comet's geocentric position.  My answers are the comet's topocentric position.

 	Two batch files are provided for your convenience.  "Cometbat.bat" is for running "Comets" and "Scope".  "Comet_SS.bat" is for running "Comets", "SolarSys" and "Scope".

-----------------------------------------------------------------------------

To run the program:
For most users  - after filtering the data set once:
 	Automatically inputting of system date and time, the data in "Locale.txt" and no filtering.  Use the following DOS command line 
 	Comets < C_Std_In

For Manual Input - the program prompts you for input.  
 	DOS Command Line: Comets

Also, You need to edit "Locale.txt" for your location.

Format for "Locale.txt"
Longitude (deg) W= pos 
Latitude  (deg) 
Altitude (feet) 
Time Zone.  USA's time zones are negative.  EST = -5

Example:
70.56
40.012
100
-5


-----------------------------------------------------------------------------

To obtain the latest data file.  Go to 
http://cfa-www.harvard.edu/iau/Ephemerides/Comets/Soft01Cmt.txt
Then save the file as "Cmt.txt".

Also, I plan to have the latest file at the following locations:
http://groups.yahoo.com/group/scope-drive/files/Comets/
http://www.geocities.com/kindellism/

If you have questions, email me at Kindellism@netzero.net

