This directory stores the starting solution of an observation that is created from the executable make_sumfiles.
Each image has its own "nominal" file stored in the NOMINALS directory. These files have the image name with the suffix ".NOM". Nominal files do not update with the use of SPC (the "v 4" command in lithos), unlike sumfiles.
All vectors are in body fixed frame.
Frame reference - Inertial s/c velocity unit vector that defines the downtrack direction. The label is the frame used for SIGMA_VSO.
SCOBJ - S/C to object vector -- [units km] (This can be in inertial frame, or body fix position.)
SIGMA_VSO - Error in S/C position -- [units km]
Cx, Cy, Cz - Camera pointing vectors in the body frame.
SIGMA_PTG - Error in camera pointing -- [units rad] There are entries for DYNAMICS that list the previous 2 and following 2 images' relative positions. These are used to condition the S/C position when running GEOMETRY, option 2.
Here is a sample of a nominal file:
S595057374F1 -0.3635326241D+00 -0.9250382113D+00 -0.1102195033D+00 BOD_FRAME 0.3071334125D+00 0.4756036668D+02 -0.3008768662D+01 SCOBJ 0.1000000000D+01 0.1000000000D+01 0.1000000000D+01 SIGMA_VSO 0.9685067274D+00 0.3109628683D-02 0.2489679684D+00 CX 0.2486662018D+00 -0.6285289007D-01 -0.9665477920D+00 CY 0.1264275161D-01 0.9980179580D+00 -0.6164670642D-01 CZ 0.1000000000D-02 0.1000000000D-02 0.1000000000D-02 SIGMA_PTG END FILE
Figure 00: Nominal File Illustrating the Starting Solution
(Compiled by KD)