ABOUT LAMBDA

FITS Headers

DIRBE_BAND06_AAM_P3B.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    = '11/02/97'           / FITS file creation date (dd/mm/yy)             
DATE-MAP= '04/04/96'           / 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 = 'B06_AAM '           / Band 6 Annual Average Sky Map                  
VERSION = 'Pass 3B '           / Version of Data Reduction Software             
WAVE6   = '25.  microns'       / nominal wavelength of Band 6                   
SOLELONG= 'ALL     '           / all available solar elongations included       
APPVEC  = 'COMBINED'           / data having different approach vectors         
COMMENT                        / are combined during processing                 
ZLREMOV =                    F / zodiacal foreground removal indicator          
COMMENT                        / if 'T(rue)', zodi foreground has been removed  
COMMENT                        / if 'F(alse)', observed sky brightness is given 
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  =                   27 / 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 =                    7 / Number of fields (columns) in the table        
COMMENT                                                                         
COMMENT                                                                         
TIMVERSN= 'OGIP/93-003'        / GSFC Ofice of Guest Investigator Programs (OGIP
COMMENT                        / memo in which the convention is described      
COMMENT         The times reported in this file are International               
COMMENT         Atomic Time (TAI) seconds elapsed since                         
COMMENT         00:00:00 UTC, 1 January 1981.  Time information is              
COMMENT         recorded in a manner consistent with the convention specified   
COMMENT         in OGIP/93-003 with the understanding that time is counted      
COMMENT         in atomic seconds and the origin of time (MJDREF) is quoted     
COMMENT         in ephemeris MJD.                                               
TIMESYS = '1981.00 '           / time system (same as IRAS)                     
MJDREFI =                44605 / Integer portion of ephemeris MJD               
COMMENT                        / corresponding to 0h UTC 1 Jan 1981             
MJDREFF =        0.00059240741 / Fractional portion of ephemeris MJD            
COMMENT                        / corresponding to 0h UTC 1 Jan 1981             
TIMEUNIT= 's       '           / unit for TSTART, TSTOP, TIMEZERO = seconds     
TSTART  =        282185275.611 / observation start time in TIMESYS system       
TSTOP   =        306753235.358 / observation stop time in TIMESYS system        
COMMENT                                                                         
COMMENT                                                                         
COMMENT   -------------------------------------------------------------------   
COMMENT   *******************************************************************   
COMMENT          Annual Average Sky Map -- 25. microns                          
COMMENT          Mission-averaged photometric measurements and cumulative       
COMMENT          sky coverage data for DIRBE Band 6 (25. microns).              
COMMENT          The photometry is computed from the weighted average of all    
COMMENT          available weekly-averaged maps for the entire mission,         
COMMENT          up to the time when the cryogen supply was exhausted.          
COMMENT          The foreground signal from Zodiacal dust remains in the map.   
COMMENT   *******************************************************************   
COMMENT   -------------------------------------------------------------------   
COMMENT   ===================================================================   
COMMENT   Coordinate Information (Spatial and Temporal):                        
COMMENT   ===================================================================   
COMMENT   -------------------------------------------------------------------   
COMMENT       DIRBE Pixel number (resolution 9)                                 
TTYPE1  = 'Pixel_no'           / pipeline fieldname = Pixel_no                  
TUNIT1  = '        '           /                                                
TFORM1  = '1J      '           /                                                
COMMENT   --------------------------------------------------------------------- 
COMMENT        Sub-pixel containing the mean DIRBE LOS (line-of-sight)          
COMMENT         when pixel is divided into 256                                  
COMMENT         sub-pixels (16x16 grid) according to                            
COMMENT         standard quad-sphere rules.                                     
TTYPE2  = 'PSubPos '           / pipeline fieldname = Pixel_subpos              
TUNIT2  = '        '           /                                                
TFORM2  = '1B      '           /                                                
COMMENT   --------------------------------------------------------------------  
COMMENT       Time in International Atomic Time (TAI) seconds                   
COMMENT       elapsed since 01-JAN-1981:00:00:00.000 UTC.                       
COMMENT       This is the average time of all observations of a pixel           
COMMENT       within the time interval TSTART to TSTOP,                         
COMMENT       regardless of the weight assigned to a particular observation.    
COMMENT       For this product, not a physically meaningful quantity.           
TTYPE3  = 'Time    '           / pipeline fieldname = Time                      
TUNIT3  = '        '           /                                                
TFORM3  = '1D      '           /                                                
COMMENT   -------------------------------------------------------------------   
COMMENT   ===================================================================   
COMMENT   DIRBE Sky Brightness Information:                                     
COMMENT   ===================================================================   
COMMENT   -------------------------------------------------------------------   
COMMENT       Cumulative weighted average of the 25. micron photometry.         
COMMENT        This average is calculated using the weighted number of          
COMMENT        observations from each Weekly Averaged Map ( WtNumObs from       
COMMENT        the Weekly Averaged Map) as the weight, such that                
COMMENT        annual_average =                                                 
COMMENT           sum( weekly_average * weekly_weight )/ sum( weekly_weight )   
COMMENT                                                                         
COMMENT        The photometric measurement is given as a                        
COMMENT        spectral intensity, I(nu) in MJy/sr, and                         
COMMENT        is 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.                           
COMMENT                                                                         
TTYPE4  = 'Photomet'           / pipeline fieldname = Photometry                
TUNIT4  = 'MJy/sr  '           /                                                
TFORM4  = '1E      '           /                                                
COMMENT   --------------------------------------------------------------------  
COMMENT        The standard deviation of the (weighted) average photometry      
COMMENT         values.                                                         
TTYPE5  = 'StdDev  '           / pipeline fieldname = Standard_deviation        
TUNIT5  = 'MJy/sr  '           /                                                
TFORM5  = '1E      '           /                                                
COMMENT   --------------------------------------------------------------------  
COMMENT        Sum of the weekly weighted number of observations that went into 
COMMENT         forming the annual averages.                                    
TTYPE6  = 'WtNumObs'           / pipeline fieldname = Weighted_num_obs          
TUNIT6  = '        '           /                                                
TFORM6  = '1I      '           /                                                
COMMENT   --------------------------------------------------------------------- 
COMMENT        Sum of the total number of observations available, regardless    
COMMENT         of assigned weight.                                             
TTYPE7  = 'SumNRecs'           / pipeline fieldname = Sum_numrecs               
TUNIT7  = '        '           /                                                
TFORM7  = '1J      '           /                                                
COMMENT   --------------------------------------------------------------------- 
END                                                                             

A service of the HEASARC and of the Astrophysics Science Division at NASA/GSFC
Goddard Space Flight Center, National Aeronautics and Space Administration
HEASARC Director: Dr. Alan P. Smale
LAMBDA Director: Dr. Eric R. Switzer
NASA Official: Dr. Eric R. Switzer
Web Curator: Mr. Michael R. Greason