pole

Description

This program solves for the pole right ascension, declination and rotation rate for a body in principal axis rotation. The rotation rate is calculated in degrees/day while right ascension and declination are calculated in degrees.

Input Files

• POLE.TXT - simple text file containing nominal pole RA (deg), DEC (deg), PM (deg), OMEGA (deg/day)

• LMRKLIST.TXT - list of landmarks

POLE.TXT and LMRKLIST.TXT must be in the working directory.

POLE.TXT is a single row file that contains the predicted pole RA (deg), DEC (deg), PM (deg), and OMEGA (deg/day). These values are given in the .tpc kernel file for the object. LMRKLIST.TXT contains a list of landmarks.

Using pole

1. Input a time in UTC.

• Make sure the time is within the span supported by the kernels.

2018 NOV 16 13:09:54.824

2. Create a POLE.TXT file.

Sample POLE.TXT file:

       86         -65      89.00000000    2010.48945

3. Answer whether you want the rotation rate fixed (y for yes, n for no).

4. Enter

• 0 if you want to iterate

• 1 if you want to keep the result (this updates POLE.TXT)

• 2 if you want the previous result (this is nominal if on the first iteration)

Here is a sample output from the POLE.TXT input:

    86.60062   -65.00002    90.42707  2009.99979311
     0.05176     0.02171                 0.00000001

The first row gives all the new pole parameters for POLE.TXT. The second row shows the change.

(Compiled by KD)

CategoryPrograms