FITS file - 3rd extension

Example header:

XTENSION= 'IMAGE   '           / IMAGE extension                                
BITPIX  =                  -32                                                  
NAXIS   =                    2                                                  
NAXIS1  =                   31                                                  
NAXIS2  =                   31                                                  
PCOUNT  =                    0 / required keyword; must = 0                     
GCOUNT  =                    1 / required keyword; must = 1                     
EXTNAME = '2MASS J image'      /                                                
ORIGIN  = '2MASS   '           / 2MASS Survey Camera                            
TELESCOP= '2MASS   '           / North=Mt.Hopkins,South=CTIO                    
GID     = '004125  '           / 2MASS ID #                                     
NNAME   = 'n/a     '           / NED Cat Name                                   
SCANNO  = '104     '           / Scan Number                                    
COADDNO = '186     '           / Coadd Number                                   
ORDATE  = '990920s '           / Observation Ref Date (yymmdd)                  
UTDATE  = '990920  '           / UT Date of Frame (IC) (yymmdd)                 
UT      = '07:06:36.54'        / Time of Frame (IC) (sxgsml)                    
DATE-OBS= '1999-09-20T07:06:36.54' / Observation Ref Date                       
EQUINOX =                2000. / Equinox                                        
CTYPE1  = 'RA---SIN'           / Orthographic Projection                        
CTYPE2  = 'DEC--SIN'           /                                                
RA      =        0.03768740967 / RA  at Frame Center, J2000 (deg)               
DEC     =         -46.08099365 / Dec at Frame Center, J2000 (deg)               
CRVAL1  =        0.03768740967 / RA  at Frame Center, J2000 (deg)               
CRVAL2  =         -46.08099365 / Dec at Frame Center, J2000 (deg)               
CRPIX1  =                  16. / Axis 1 Reference Pixel                         
CRPIX2  =                  16. / Axis 2 Reference Pixel                         
CROTA2  =      -0.007425205782 / Image Twist  E of N, J2000 (deg)               
CDELT1  =     -0.0002777777845 / Axis 1 Pixel Size (deg)                        
CDELT2  =      0.0002777777845 / Axis 2 Pixel Size (deg)                        
JSKYVAL =          81.16457367 / GALWORKS J Sky Measurement                     
JSKYSIG =         0.5749330521 / GALWORKS J Noise Measurement                   
HSKYVAL =          274.0104065 / GALWORKS H Sky Measurement                     
HSKYSIG =         0.7801685333 / GALWORKS H Noise Measurement                   
KSKYVAL =          542.3426514 / GALWORKS K Sky Measurement                     
KSKYSIG =          1.058423996 / GALWORKS K Noise Measurement                   
CALID   = ' V3-CALIBRATED'     / Calibration ID                                 
JSEESH  =         0.9700000286 / Seeing J shape parameter                       
HSEESH  =         0.9580000043 / Seeing H shape parameter                       
KSEESH  =         0.9990000129 / Seeing K shape parameter                       
JMAGZP  =              20.8910   / Calibrated J zero point from CALMAN          
HMAGZP  =              20.4510   / Calibrated H zero point from CALMAN          
KMAGZP  =              19.9340   / Calibrated K zero point from CALMAN          
AMASS_FC=          1.170329571 / Airmass (aprox) at this position               
COMMENT > Planes 1, 2 and 3 represent the background                            
COMMENT > subtracted images of the J, H and Ks bands;                           
COMMENT > Planes 4,5,6 represent the background **and**                         
COMMENT > star subtracted images of the J, H and Ks bands                       
HISTORY > GALWORKS Version 3                                                    
HISTORY > image created by galworks,  Tom Jarrett, IPAC/Caltech/JPL             
END