FITS Headers
DIRBE_BAND3A_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 = 'B3A_AAM ' / Band 3A Annual Average Sky Map VERSION = 'Pass 3B ' / Version of Data Reduction Software WAVE3 = '3.5 microns' / nominal wavelength of Band 3 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 -- 3.5 microns COMMENT Mission-averaged photometric measurements and cumulative COMMENT sky coverage data for DIRBE Band 3A (3.5 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 3.5 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
