The files included here, with names 'usgssurfaceXXX.png' are basic shaded      
surface plots of the elevation data contained in the usgsdem.tab file.         
This is a simple representation of the shape of the areas of the               
surface of comet 19P/Borrelly that were visible during the Deep Space          
1 encounter.                                                                   
                                                                               
The images were created using the shade_surf routine in IDL.  First,           
the map was read into IDL, and then rotated to                                 
place it in the same orientation as the NEAR_1 frame.  The surface             
plot was generated with a viewing location 60 degrees above the X-Y            
plane and an azimuthal position given by the XXX in the filename.              
                                                                               
IDL Commands used to generate these images are of the form:                    
                                                                               
Read the elevation map into an IDL array named shape1                          
IDL> shape1 = rotate(shape1,7)                                                 
IDL> x = findgen(356)*16.-2792                                                 
IDL> y = findgen(478)*16.-2840                                                 
IDL> shade_surf,shape1,x,y, ax=60,az=0,$                                       
       xrange=[-2792,2888], yrange=[-2840,4792],zrange=[0,6000],$              
       xstyle=-1,ystyle=-1,zstyle=-1