FITS Headers


Primary Header

SIMPLE  =                    T / file does conform to FITS standard             
BITPIX  =                  -32 / REAL*4 data                                    
NAXIS   =                    3 / number of data axes                            
NAXIS1  =                  225 / in-scan axis                                   
NAXIS2  =                  181 / cross-scan axis                                
NAXIS3  =                    3 / time-period axis                               
DATE-MAP= '30/06/95'           / Date of original data file creation (dd/mm/yy) 
DATE    = '11/02/97'           / FITS file creation date (dd/mm/yy)             
ORIGIN  = 'CDAC'               / Cosmology Data Analysis Center                 
TELESCOP= 'COBE'               / Cosmic Background Explorer satellite           
INSTRUME= 'DIRBE'              / COBE instrument [DIRBE, DMR, FIRAS]            
OBJECT  = 'BEAM'               / DIRBE beam profile map                         
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      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)    
COMMENT      DIRBE specific keywords                                            
PRODUCT = 'BEAM3B'             / DIRBE Band 3B beam profile                     
VERSION = 'Pass 3B'            / Version of Data Reduction Software             
WAVE3   = '3.5  microns'       / nominal wavelength of Band 3                   
SOLELONG= 'ALL'                / all available solar elongations used           
APPVEC  = 'COMBINED'           / data having different approach vectors         
COMMENT                        / are combined during processing                 
COMMENT  -------------------------------------------------------------------    
COMMENT  *******************************************************************    
COMMENT    Beam Profile -- DIRBE Band 3B.                                       
COMMENT    This is an effective beam profile, which measures the                
COMMENT    relative response of the DIRBE to a point source, including          
COMMENT    the effects of sky-scanning and data-sampling rates.                 
COMMENT    Beam profiles are represented as two-dimensional                     
COMMENT    arrays which give the beam response as a                             
COMMENT    function of in-scan and cross-scan position.                         
COMMENT    In-scan position is defined as positive                              
COMMENT    toward the scan direction, and cross-scan position is                
COMMENT    defined as positive toward the spacecraft spin-axis.                 
COMMENT    The origin (0,0) corresponds to the nominal boresight                
COMMENT    position as defined from the attitude solution.                      
COMMENT    Beam profiles for Band 3B were noted to be                           
COMMENT    slightly time-dependent.  Therefore, 3 beam profiles are             
COMMENT    recorded here, covering the following time intervals (YYDDD):        
COMMENT     beam #1: 89345 - 90175 (inclusive)                                  
COMMENT     beam #2: 90176 - 90231 (inclusive)                                  
COMMENT     beam #3: 90232 - 90264 (inclusive)                                  
COMMENT    Beam #1 is normalized to a value of 1.0 at the                       
COMMENT    location of peak response.  Beams #2 and #3                          
COMMENT    are normalized such that the beam profile solid angle                
COMMENT    is constant during the cold mission, using the solid angle           
COMMENT    found for Beam #1.  The peak response of beams #2 and #3             
COMMENT    differs from unity by less than 1%.                                  
COMMENT    The beam solid angle for Band 3B used in the Pass3B data             
COMMENT    processing is  1.291 e-04 sr.                                        
COMMENT  *******************************************************************    
COMMENT  -------------------------------------------------------------------    
CRVAL1  =             0.000000 / Value at origin (arcmin)                       
CRPIX1  =                  113 / position of origin                             
CTYPE1  = 'INSCAN'             / in-scan coordinate; range +- 42 arcmin         
CDELT1  =             0.375000 / in-scan sampling increment, arcmin per pixel   
COMMENT  -------------------------------------------------------------------    
CRVAL2  =             0.000000 / Value at origin (arcmin)                       
CRPIX2  =                   91 / position of origin                             
CTYPE2  = 'XSCAN'              / x-scan coordinate; range +- 36 arcmin          
CDELT2  =             0.400000 / x-scan sampling increment, arcmin per pixel    
COMMENT  -------------------------------------------------------------------    
CRVAL3  =                    1 /                                                
CRPIX3  =                    1 /                                                
CTYPE3  = 'BEAM-NO'            / beam number; range 1-3                         
CDELT3  =                    1 /                                                
COMMENT  -------------------------------------------------------------------    

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