ABOUT LAMBDA

FITS Header

Primary Header

SIMPLE  =                    T / file does conform to FITS standard             
BITPIX  =                    8 / 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 is defined in 'Astronomy
COMMENT   and Astrophysics', volume 376, page 359; bibcode: 2001A&A...376..359H 
DATE    = '2005-03-04'         / file creation date (YYYY-MM-DD)                
TELESCOP= 'IRAS    '           / Infrared Astronomical Satellite                
OBJECT  = 'ALL-SKY '           / Portion of sky given                           
COMMENT   This file contains a HEALPix map of 100 micron intensity formed from  
COMMENT   IRAS Sky Survey Atlas (ISSA) data.  It was made by averaging the      
COMMENT   coadded (HCON 0) ISSA data over HEALPix pixels.  Overlapping data     
COMMENT   between neighboring ISSA fields were excluded.  All of the ISSA fields
COMMENT   were used, including the Reject fields at low ecliptic latitudes where
COMMENT   residuals after subtraction of the zodiacal emission model are        
COMMENT   significant.  Minor discontinuities are present at field boundaries   
COMMENT   at some locations in the map, due to intensity differences between    
COMMENT   neighboring fields at low ecliptic or Galactic latitude.  Sky coverage
COMMENT   is about 98%, and intensity values are set to -32768 for HEALPix      
COMMENT   pixels that contain no ISSA data.                                     
REFERENC= 'Legacy Archive for Microwave Background Data Analysis (LAMBDA)      '
REFERENC= '                http://lambda.gsfc.nasa.gov/                        '
REFERENC= 'IRAS Sky Survey Atlas Explanatory Supplement,                       '
REFERENC= ' Wheelock, S.L., et al., 1994, JPL Publication 94-11 (Pasadena: JPL)'
REFERENC= ' http://lambda/product/iras/docs/issa.exp.sup/                      '
REFERENC= 'HEALPix Home Page: http://www.eso.org/science/healpix/              '
FREQ    = '100 micron band'    / Wavelength band                                
RESOLUTN=                   10 / Resolution index                               
SKYCOORD= 'Galactic'           / Coordinate system                              
PIXTYPE = 'HEALPIX '           / Pixel algorithm                                
ORDERING= 'NESTED  '           / Ordering scheme                                
NSIDE   =                 1024 / Resolution parameter                           
NPIX    =             12582912 / # of pixels                                    
FIRSTPIX=                    0 / First pixel (0 based)                          
LASTPIX =             12582911 / Last pixel (0 based)                           
END                                                                             

Archive Map Table

XTENSION= 'BINTABLE'           /binary table extension                          
BITPIX  =                    8 /8-bit bytes                                     
NAXIS   =                    2 /2-dimensional binary table                      
NAXIS1  =                    8 /width of table in bytes                         
NAXIS2  =             12582912 /number of rows in table                         
PCOUNT  =                    0 /size of special data area                       
GCOUNT  =                    1 /one data group (required keyword)               
TFIELDS =                    2 /number of fields in each row                    
TTYPE1  = 'Intensity'          /label for field   1                             
TFORM1  = '1E      '           /data format of field: 4-byte REAL               
TUNIT1  = 'MJy sr-1'           /physical unit of field                          
TTYPE2  = 'N_PIXELS'           /label for field   2                             
TFORM2  = '1E      '           /data format of field: 4-byte REAL               
TUNIT2  = 'ISSA pixel count'   /physical unit of field                          
EXTNAME = 'Archive Map Table'  /name of this binary table extension             
DATE    = '2005-03-04'         /Table/MAP creation date (YYYY-MM-DD)            
PIXTYPE = 'HEALPIX '           /Pixel algorithm                                 
ORDERING= 'NESTED  '           /Ordering scheme                                 
NSIDE   =                 1024 /Resolution parameter                            
FIRSTPIX=                    0 /First pixel (0 based)                           
LASTPIX =             12582911 /Last pixel (0 based)                            
COMMENT   Intensity is average of ISSA 100 micron data over HEALPix pixels      
COMMENT   N_PIXELS is number of ISSA pixels contributing to each HEALPix pixel  
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