HELIO_IMAGE (Mar95)              suntrans              HELIO_IMAGE (Mar95)



IMAGE IN A HELIOGRAPHIC COORDINATE SYSTEM-- 
    image registered on a heliographic coordinate system.  Images  in  a
    heliographic  coordinate system are in one of the three arrangements
    shown below.
    
    
    entire-sphere images in a heliographic coordinate system
        Images covering an entire sphere in latitude  and  longitude  as
        illustrated below.  Points are equally spaced in latitude.
        
                         North
        _________________________________________
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|          X sun
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|<--equator          
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|           
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|          
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|          
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |---------------------------------------|
                        South
    
    unfolded images on a heliographic coordinate system
        Images   covering   a   hemisphere   or  less  registered  on  a 
        heliographic coordinate system.  Points may  be  equally  spaced
        in latitude or sin(latitude)
                         North
        _________________________________________
        |......XXXXXXXXXXXXXXXXXXXXXXXXXXX......|
        |...XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX...|
        |.XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|             
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|<--equator    
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|    X sun           
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|    . zeros near the   
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|      limb returned  
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|      by interpolator 
        |.XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.|      or masked out
        |...XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX...|
        |......XXXXXXXXXXXXXXXXXXXXXXXXXXX......|
        |---------------------------------------|
                        South
    
    folded images on a heliographic coordinate system
        Images   covering   a   hemisphere   or  less  registered  on  a 
        heliographic coordinate system.  Points may  be  equally  spaced
        in  latitude  or  sin(latitude)  in  the  format required by the
        spherical harmonic transform code.
                    North-South
        _________________________________________
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|      X sun
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|      . zeros returned by
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|        interpolator or 
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|        areas masked out
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|        near the limb
        |XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX|
        |.XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.|  
        |.XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX.|  etc.
        |...XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX...|  - angle 2 (South)
        |...XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX...|  + angle 2 (North)
        |......XXXXXXXXXXXXXXXXXXXXXXXXXXX......|  - angle 1 (South)
        |......XXXXXXXXXXXXXXXXXXXXXXXXXXX......|  + angle 1 (North)
        |---------------------------------------|
                       Equator
        
        
        
SAMPLE IMAGE HEADER
    
    doct130[372,220][real]: brd<