May 6, 1991 Code 933 NASA/GSFC Greenbelt, MD 20771 To: Astronomical Data Analysis Software Developers From: National Space Science Data Center, ADC CD-ROM Team Subject: Experimental FITS Tables The three experimental FITS tables, ADCTEST1.FIT, ADCTEST2.FIT and ADCTEST3.FIT, were generated at the National Space Science Data Center, NASA Goddard Space Flight Center, as part of the development of FITS tables for the Astronomical Data Center CD-ROM of astronomical catalogs. The principles being tested are the viability of (1) using mixed-case strings in the value fields of the TTYPEn and TUNITn keywords, (2) putting nontextual ASCII characters (carriage return/linefeed pairs) in the table data portion of the FITS file, and (3) placing CR/LF pairs into the headers themselves. Because of the imbedded carriage control, make sure that the files are retrieved as "type image" under FTP. For type (1) FITS files, we are looking for problems in storing and retrieving mixed case values for TTYPE and TUNIT. Are the headers simply rejected when first read in, or do other problems crop up later in the data processing? For type (2) FITS files, we are looking for problems in the input of table data records with imbedded carriage control characters. Are read operations disrupted? Are there any other problems? For type (3) FITS files, CR/LF pairs have been placed in bytes 79-80 of each card image in the FITS header. This renders a "printable and editable FITS table", since the file can be previewed with standard "type" or "cat" OS commands and/or directed straight to a system printer without preprocessing to strip away the 2880-byte fixed length header records. We are especially interested in seeing if the carriage control characters in the headers interfere with the proper interpretation of the header information. The tables all contain the same catalog, the "Strasbourg Catalog of Galactic Planetary Nebulae," Acker, A., Marcout, J. Ochsenbein, F. 1980, Centre de Donnees Stellaires Bull. No.18, 84. A listing of the table extension header is given at the end of this file. We ask that these FITS tables each be processed by your FITS reading software and that any problems encountered be reported back to Lee Brotzman at the address below. Note that all of these FITS tables were processed without error using the FITS Table Browser (FTB) program for IBM PC-class computers developed at NSSDC; no modifications to the code were made before the tests were run. Unless there are any objections from the community, we are leaning toward type (2) FITS tables (CR/LF pairs imbedded in the data portion of the FITS table, but not in the header). Type (3), while attractive, is in direct violation of the accepted IAU FITS standards and the proposed NASA Standard Implementation of FITS. However, the headers so contructed should still be readable. -- Lee Brotzman Internet: zmleb@scfvm.gsfc.nasa.gov -- ST Systems Corp. BITNET: ZMLEB@SCFVM -- National Space Science Data Center SPAN: NSSDCA::BROTZMAN ---------------------< Begin PLN.HDR >----------------------- XTENSION= 'TABLE ' / Table extension BITPIX = 8 / Character data NAXIS = 2 / Simple 2-D matrix NAXIS1 = 52 / Number of characters per record NAXIS2 = 1455 / Number of records in the table PCOUNT = 0 / No "random" parameters GCOUNT = 1 / Only one group TFIELDS = 16 / Number of data fields per record EXTNAME = 'PLN ' / Strasbourg Galactic Planetary Nebulae AUTHOR = 'Acker et al.' / Catalog author(s) REFERENC= '1980 CDS Bull.' / Catalog reference(s) DATE = '03/10/88' / Date FITS table verified (dd/mm/yy) HISTORY Source Catalog Reference: Acker, A., Marcout, J. Ochsenbein, F. 1980, HISTORY Centre de Donnees Stellaires Bull. No.18, 84. HISTORY HISTORY A copy of "Documentation for the Machine-Readable Version of the HISTORY Strasbourg Catalogue of Galactic Planetary Nebulae", Hill 1983, HISTORY Doc. No. SSD-T-1-0338-0097-83 should accompany any computer-readable HISTORY version of the catalog. TTYPE1 = 'PK ' / Perek-Kohoutek (PK) number TBCOL1 = 1 / Start column TFORM1 = 'A9 ' / Fortran format TTYPE2 = 'RAH ' / Hours RA, 1950.0 TBCOL2 = 10 / Start column TFORM2 = 'I2 ' / Fortran format TUNIT2 = 'h ' / Units are hours TTYPE3 = 'RAM ' / Minutes RA, 1950.0 TBCOL3 = 13 / Start column TFORM3 = 'F5.2 ' / Fortran format TUNIT3 = 'min ' / Units are minutes of time TTYPE4 = 'DecSign ' / Sign Dec, 1950 TBCOL4 = 19 / Start column TFORM4 = 'A1 ' / Fortran format TTYPE5 = 'DecD ' / Degrees Dec, 1950.0 TBCOL5 = 20 / Start column TFORM5 = 'I2 ' / Fortran format TUNIT5 = 'deg ' / Units are degrees TTYPE6 = 'DecM ' / Minutes Dec, 1950.0 TBCOL6 = 23 / Start column TFORM6 = 'F4.1 ' / Fortran format TUNIT6 = 'arcmin ' / Units are minutes of arc TTYPE7 = 'V_Limit ' / '>' if V is a lower limit TBCOL7 = 28 / Start column TFORM7 = 'A1 ' / Fortran format TTYPE8 = 'V ' / Visual magnitude TBCOL8 = 29 / Start column TFORM8 = 'F4.1 ' / Fortran format TUNIT8 = 'mag ' / Units are magnitudes TNULL8 = ' ' / Null value TTYPE9 = 'Morph_Flag' / Morphology flag TBCOL9 = 34 / Start column TFORM9 = 'A1 ' / Fortran format TNULL9 = ' ' / Null value COMMENT Morph_Flag: '<' for star-like appearance, '>' for fainter spherical COMMENT Morph_Flag: envelope, or else blank. TTYPE10 = 'Diam ' / Angular diameter of brightest part TBCOL10 = 35 / Start column TFORM10 = 'I3 ' / Fortran format TUNIT10 = 'arcsec ' / Units are seconds of arc TNULL10 = ' ' / Null value TTYPE11 = 'RadVel ' / Mean radial velocity TBCOL11 = 39 / Start column TFORM11 = 'I4 ' / Fortran format TUNIT11 = 'km/s ' / Units are kilometers per second TNULL11 = ' ' / Null value TTYPE12 = 'StarMag_Limit' / '>' if StarMag is a lower limit TBCOL12 = 44 / Start column TFORM12 = 'A1 ' / Fortran format TNULL12 = ' ' / Null value TTYPE13 = 'StarMag ' / Central star magnitude TBCOL13 = 45 / Start column TFORM13 = 'F4.1 ' / Fortran format TUNIT13 = 'mag ' / Units are magnitudes TNULL13 = ' ' / Null value TTYPE14 = 'Var_Flag' / 'V' if central star is variable TBCOL14 = 49 / Start column TFORM14 = 'A1 ' / Fortran format TNULL14 = ' ' TTYPE15 = 'ExpVel_Limit' / ExpVel limit flag, '<', '>', or blank TBCOL15 = 50 / Start column TFORM15 = 'A1 ' / Fortran format TNULL15 = ' ' / Null value TTYPE16 = 'ExpVel ' / Nebula expansion velocity TBCOL16 = 51 / Start column TFORM16 = 'I2 ' / Fortran format TUNIT16 = 'km/s ' / Units are kilometers per second TNULL16 = ' ' / Null value END ---------------------< End PLN.HDR >-----------------------