These files contain offsets to remove spin harmonics due to solar array 
currents.  These values were provided by David Fischer 
(David.Fischer@oeaw.ac.at).

The values are formatted into 4-columns. Column-1: Degree, Column-2 
X-Component, Column-3 Y-Component,Column-4 Z-Component.  The values are 
interpolated to the spin model and subtracted during all non-shadow 
times.

NOTE IF YOU ARE ADDING NEW CALIBRATION FILES: If you are installing new 
calibration files be sure to replace the default file: 
'thb_default_avgdist.txt' with the most recent file added.  

'thb_default_avgdist.txt' is used for periods when these calibration 
files have not been generated.  The error due to using a slightly old
file should be small because the drift over time is minimal.

The files for Feb,Mar,Apr 2007 are copies of the May 2007 file.  More 
accurate calibrations for the earliest part of the mission are not 
currently available.

Also, the files from Sep 2009 onward are missing because there were not 
enough data points to perform reasonable calculations.

For thb and thc for missing months we use the previous month's files.