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FITS Headers

DIRBE_BAND2A_ZSMA.FITS

Primary Header

SIMPLE  =                    T / file does conform to FITS standard             
BITPIX  =                   32 / number of bits per data pixel                  
NAXIS   =                    0 / number of data axes                            
EXTEND  =                    T / FITS dataset may contain extensions            
COMMENT   FITS (Flexible Image Transport System) format defined in Astronomy and
COMMENT   Astrophysics Supplement Series v44/p363, v44/p371, v73/p359, v73/p365.
COMMENT   Contact the NASA Science Office of Standards and Technology for the   
COMMENT   FITS Definition document #100 and other FITS information.             
DATE    = '29/05/97'           / FITS file creation date (dd/mm/yy)             
DATE-MAP= '28/07/96'           / Date of original file creation (dd/mm/yy)      
ORIGIN  = 'CDAC    '           / Cosmology Data Analysis Center                 
TELESCOP= 'COBE    '           / Cosmic Background Explorer satellite           
INSTRUME= 'DIRBE   '           / COBE instrument [DIRBE, DMR, FIRAS]            
OBJECT  = 'ALL-SKY '           / part of sky given [e.g., ALL-SKY, WEEKLY-SKY,  
COMMENT                        /         DAILY-SKY, GAL-SLICE, FACE ...]        
EQUINOX =               2000.0 / equinox of coords in following tables          
REFERENC= 'COBE/DIRBE Explanatory Supplement,' /                                
REFERENC= 'ed. M.G. Hauser, T. Kelsall, D. Leisawitz, and J. Weiland,' /        
REFERENC= 'COBE Ref. Pub. No. 97-A (Greenbelt,MD: NASA/GSFC),' /                
REFERENC= 'available in electronic form from the NSSDC.' /                      
COMMENT                                                                         
COMMENT     COBE specific keywords                                              
DATE-BEG= '11/12/89'           / date of initial data represented (dd/mm/yy)    
DATE-END= '21/09/90'           / date of final data represented   (dd/mm/yy)    
PIXRESOL=                    9 / Quad tree pixel resolution [6, 9]              
COMMENT                                                                         
COMMENT     DIRBE specific keywords                                             
PRODUCT = 'B2A_ZSMA'           / Band 2A map after IPD Model removal            
VERSION = 'Pass 3B '           / Version of Data Reduction Software             
WAVE2   = '2.2 microns'        / nominal wavelength of Band 2                   
SOLELONG= '68-120 degrees'     / only solar elongations in the range            
COMMENT                        / [68,120] degrees are utilized                  
APPVEC  = 'COMBINED'           / data having different approach vectors         
COMMENT                        / are combined during processing                 
ZLREMOV =                    T / zodiacal foreground removal indicator          
COMMENT                        / if 'T(rue)', zodi foreground has been removed  
COMMENT                        / if 'F(alse)', observed sky brightness is given 
ZLMODEL = 'FD6     '           / Version of DIRBE IPD Model                     
COMMENT                                                                         
COMMENT                                                                         
END                                                                             

Extension Header 2

XTENSION= 'BINTABLE'           / Extension type is Binary Table                 
BITPIX  =                    8 / Binary data                                    
NAXIS   =                    2 / Data are in a table                            
NAXIS1  =                   17 / Number of 8 bit bytes in each row              
NAXIS2  =               393216 / Number of rows                                 
PCOUNT  =                    0 / Number of bytes of data following table        
GCOUNT  =                    1 / Group count (always 1 for bintable extensions) 
TFIELDS =                    5 / Number of fields (columns) in the table        
COMMENT                                                                         
COMMENT                                                                         
COMMENT   -------------------------------------------------------------------   
COMMENT   *******************************************************************   
COMMENT     Zodi-Subtracted Mission Average (ZSMA) Skymap -- 2.2 microns        
COMMENT                                                                         
COMMENT        This map represents the extra-Solar system sky brightness        
COMMENT        at 2.2 microns.  It is the average residual map that             
COMMENT        results after the modelled interplanetary dust (IPD) signal      
COMMENT        is subtracted from each of the DIRBE Weekly Skymaps              
COMMENT        from the cryogenic mission. Individual weekly residual maps      
COMMENT        can be reconstructed from the data supplied in the               
COMMENT        DIRBE Sky and Zodi Atlas (DSZA).                                 
COMMENT                                                                         
COMMENT        Not all of the available weekly residuals were used in the       
COMMENT        construction of the mission averaged residual map.               
COMMENT        The following relatively low-quality data were excluded:         
COMMENT        1) mission week 04 (89345 - 89351), band 8                       
COMMENT        2) mission week 24 (90120 - 90126), bands 1-8                    
COMMENT        3) mission weeks 39 & 40 (90225 - 90238), bands 1-8              
COMMENT        4) data taken near solar elongation extrema                      
COMMENT           (solelong .GT. 120  .AND. solelong .LT. 68)                   
COMMENT                                                                         
COMMENT                                                                         
COMMENT                                                                         
COMMENT   *******************************************************************   
COMMENT   -------------------------------------------------------------------   
COMMENT   ===================================================================   
COMMENT   Coordinate Information (Spatial):                                     
COMMENT   ===================================================================   
COMMENT   -------------------------------------------------------------------   
COMMENT       DIRBE Pixel number  (resolution 9)                                
TTYPE1  = 'Pixel_no'           / pipeline fieldname = Pixel_no                  
TUNIT1  = '        '           /                                                
TFORM1  = '1J      '           /                                                
COMMENT   -------------------------------------------------------------------   
COMMENT   ===================================================================   
COMMENT   DIRBE Sky Brightness Information:                                     
COMMENT   ===================================================================   
COMMENT   -------------------------------------------------------------------   
COMMENT       Mean Residual Intensity after removal of IPD Model, Band 2A.      
COMMENT        The residual photometry reported here is the unweighted          
COMMENT        average of NumWks weekly zodi-subtracted residuals,              
COMMENT        as derived from the Photomet and ZL fields supplied in           
COMMENT        the DIRBE Sky and Zodi Atlas (DSZA).                             
COMMENT        The mission-averaged residuals are given as                      
COMMENT        spectral intensities, I(nu) in MJy/sr, and                       
COMMENT        are quoted at the nominal wavelength                             
COMMENT        for a source with nu*I(nu) = constant  -- i.e.,                  
COMMENT        a color correction is required if the source                     
COMMENT        spectrum differs from nu*I(nu) = constant.                       
COMMENT        Data which have been replaced by flagged values                  
COMMENT        in processing have values .LE. -16375.                           
TTYPE2  = 'Resid   '           / pipeline fieldname = resid                     
TUNIT2  = 'MJy/sr  '           /                                                
TFORM2  = '1E      '           /                                                
COMMENT   --------------------------------------------------------------------  
COMMENT        Total number of individual 1/8th second observations             
COMMENT         contributing to the mission-averaged residual.  Computed        
COMMENT         as the sum of all weekly weighted numbers of observations       
COMMENT         (WtNumObs) used in computing the average.  Values of            
COMMENT         WtNumObs are tabulated in the DSZA product.                     
COMMENT         Range = [0,600]                                                 
TTYPE3  = 'NumObs  '           / pipeline fieldname = nobs                      
TUNIT3  = '        '           /                                                
TFORM3  = '1J      '           /                                                
COMMENT   --------------------------------------------------------------------- 
COMMENT        The number of weekly-averaged residuals used in computing        
COMMENT         the mission-averaged residual.  This number varies with         
COMMENT         sky location.                                                   
COMMENT         Range = [0,41]                                                  
TTYPE4  = 'NumWks  '           / pipeline fieldname = nrec                      
TUNIT4  = '        '           /                                                
TFORM4  = '1B      '           /                                                
COMMENT   --------------------------------------------------------------------- 
COMMENT      Standard Deviation of the mean residual intensity, computed        
COMMENT       from the deviation of individual weekly residuals                 
COMMENT       from the mission-averaged residual.                               
COMMENT                                                                         
TTYPE5  = 'StdDev  '           / pipeline fieldname = sigma_resid               
TUNIT5  = 'MJy/sr  '           /                                                
TFORM5  = '1E      '           /                                                
COMMENT   -------------------------------------------------------------------   
END                                                                             

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