KEYWORD gives the name of the FITS keyword and may be up to 8 characters.
TYPE refers to the data type and the size of the data:
S String I Integer R RealThe size of the data depends upon the data type. For example S*2 is a 2 character string, whereas I*2 is a 2 byte integer (16 bits).
VALUES shows the range of values that the KEYWORD can take.
DESCRIPTION gives a short description of the keyword.
KEYWORD TYPE VALUES DESCRIPTION SIMPLE S*1 T Conforms to FITS standard BITPIX I*2 8,16,32 Number of bits per pixel NAXIS I*2 2 Number of axes in the image NAXIS1 I*2 Positive Length of the first axis (columns) Number NAXIS2 I*2 Positive Length of the second axis (rows) Number TELESCOP S*8 SOHO Name of the satellite INSTRUME S*8 LASCO Name of the instrument DETECTOR S*8 C1,C2,C3 Name of the telescope within LASCO FILENAME S*30 Any Name of the FITS file. For the archive data we conform to the DOS 8.3 standard. FILEORIG S*17 Any Name of the raw telemetry file in the format YYMMDD_HHMMSS.img. The implied date and time are the date and time stamp of when the data were put into the telemetry stream. DATE S*23 Any Date of file generation in CSSDS standard format, eg 1996/05/21 17:28:48.208 DATE-OBS S*10 Any Date of the start of the exposure, eg: 1996/05/20 TIME-OBS S*12 Any Time of the start of the exposure, eg: 00:40:05.407 MID_DATE I*2 Any Modified Julian Date at the mid- point of the exposure MID_TIME R*4 Any Number of seconds of the day at the mid-point of the exposure OBT_TIME R*4 Any Value of the On-Board Time EXPTIME R*4 Any Number of seconds of the exposure time EXP0 R*4 Any Measured exposure delay time EXPCMD R*4 Any Commanded exposure delay time EXP1 R*4 Any Length of time since CCD clear EXP2 R*4 Any Length of time to open shutter EXP3 R*4 Any Length of time to close shutter READPORT S*1 A,B,C,D CCD readout port SUMROW I*2 0,2,4 Number of rows being summed on the CCD SUMCOL I*2 0,2,4 Number of columns being summed on the CCD LEBXSUM I*2 1,2,4,.. Number of columns being summed in the LEB LEBYSUM I*2 1,2,4,.. Number of rows being summed in the LEB SHUTTR I*2 0 Shutter was commanded open during the exposure 1 Shutter was not commanded during the exposure LAMP I*2 0 Calibration lamp was not commanded on 1 Calibration lamp was commanded on FILTER S*8 Clear Position of the filter wheel Orange FeXIV FeX CaXV Blue Red IR Lens POLAR S*8 Clear Position of the polarizer wheel 0 deg +60 deg -60 deg H alpha ND LP_NUM S*8 Normal Description of the LEB Program (LP) used to Cal Lamp generate the image Dark Line Scan Pol Seq OS_NUM I*2 Any Observing Sequence Number An arbitrary number that specifies similar instrument configuration and can be used to search the data base for other exposures taken under the same conditions. IMGCTR I*2 Any Sequential counter since the last LEB reboot IMGSEQ I*2 Any Number of the image in the current sequence, starting at 0 COMPRSSN S*8 Code indicating the steps used in compressing the data PLATESCL R*4 Any Number of arc seconds per pixel OFFSET I*2 Any Electronic offset in DN P1COL I*2 Any CCD column number of start of image, 0-19 are underscan pixels, 20-1043 are imaging pixels, 1044 - 32000 are overscan pixels P1ROW I*2 Any CCD row number of start of image, 1-1044 are imaging rows, 1025-32000 are overscan rows P2COL I*2 Any CCD column number at end of image, 0-19 are underscan pixels, 20-1043 are imaging pixels, 1044 - 32000 are overscan pixels P2ROW I*2 Any CCD row number at end of image, 1-1044 are imaging rows, 1025-32000 are overscan rows RECTIFY S*8 TRUE Status of rectification to put solar north FALSE to the top of the image R1COL I*2 Any The rectified coordinate, equivalent to P1COL, as though the image had been read out with this coordinate R1ROW I*2 Any Rectified P1ROW R2COL I*2 Any Rectified P2COL R2ROW I*2 Any Rectified P2ROW EFFPORT S*8 A,B,C,D Rectified read out port VERSION I*2 Any Version number of LEB header DATAMIN R*4 Any Minimum value of the image, including the bias DATAMAX R*4 Any Maximum value of the image DATAZER I*4 Any Number of zero pixels in the image DATASAT I*4 Any Number of saturated values in the image DATAAVG R*4 Any Average value of the image DATASIG R*4 Any Standard deviation in computing the average DATAP01 I*4 Any Intensity of 1st percentile of image DATAP10 I*4 Any Intensity of 10th percentile image DATAP25 I*4 Any Intensity of 25th percentile of image DATAP75 I*4 Any Intensity of 75th percentile of image DATAP90 I*4 Any Intensity of 90th percentile of image DATAP95 I*4 Any Intensity of 95th percentile of image DATAP98 I*4 Any Intensity of 98th percentile of image DATAP99 I*4 Any Intensity of 99th percentile of image CRPIX1 R*4 Any Column number of the reference pixel. SOHO practice has been to use this as the center of the sun. CRPIX2 R*4 Any Row number of the reference pixel. SOHO practice has been to use this as the center of the sun. CRVAL1 R*4 Any Number of arc seconds of the center of the sun from the reference position in the azimuthal direction (E-W). Positive is to the solar west CRVAL2 R*4 Any Number of arc seconds of the center of the sun from the reference position in the elevation direction (N-S). Positive is to solar north CROTA1 R*4 Any Rotation of axis 1 with respect to solar north Positive is westward (clockwise) CROTA2 R*4 Any Rotation of axis 2 with respect to solar north Positive is westward (clockwise) CTYPE1 S*8 SOLAR-X Type of units of axis #1 CTYPE2 S*8 SOLAR-Y Type of units of axis #2 CUNIT1 S*8 ARCSEC Units along axis #1 CUNIT2 S*8 ARCSEC Units along axis #1 CDELT1 R*8 Any Increment along axis #1 (Same as PLATESCL) CDELT2 R*8 Any Increment along axis #1 (Same as PLATESCL) HISTORY S*80 Any History of processing. Can be repeated COMMENT S*80 Any Comments. Can be repeated END Last keyword in the FITS header