2025-09-21T02:54:17.136555Z

unlisted ⁨1⁩ ⁨file⁩ 2025-09-21 02:54:17 UTC expires 2025-09-28 02:54:17 UTC

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Currently looking at adding a ceres gravity model using dawn data found here: <https://sbnarchive.psi.edu/pds3/dawn/grav/> (DWNCGRS_2_v4_20240517)

Looking at the lbl for the coefficients
```
Some details describing this model are:                                       
   The spherical harmonic coefficients are fully normalized.                  
   The associated GM = 62.6290536121 km^3/s^2                                 
   The reference radius = 470.0 km                                            
   The Ceres-fixed reference frame prime meridian and pole                    
      location in IAU coordinates is given by                                 
         Right ascension = 291.42763 degrees (estimated)                      
         RA rate         =   0.0 degrees/cty (fixed)                          
         Declination     =  66.76033 degrees (estimated)                      
         Dec rate        =   0.0 degrees/cty (fixed)                          
         Prime Meridian  = 170.309 degrees (estimated)                        
         Rotation rate   = 952.1532635 degrees/day (estimated)                
   The pole location, W0 and spin rate are estimated jointly with the         
   gravity field by fixing the y-value of the Kait landmark to zero.          
   The uncertainties of the pole for this solution are                        
         Right ascension = 0.0002 degrees                                     
         Declination     = 0.0002 degrees                                     
   Note ceres18d is similar to ceres18c version 2 of the gravity field        
   which has the corrected location of the kait crater. This is a             
   rotation of -0.064074 deg about the z-axis versus the previous             
   version of the gravity field.      
```

I'm particularly worried about `Prime Meridian  = 170.309 degrees (estimated)`  value, what should the prime meridian for the model be to match with KSP? Is there any way to ensure the gravity model matches with the actual terrain data?