PDS_VERSION_ID = PDS3 RECORD_TYPE = STREAM OBJECT = TEXT NOTE = "Comments on the Stardust SPICE Archive" PUBLICATION_DATE = 2009-07-29 END_OBJECT = TEXT END COMMENTS ON THE STARDUST SPICE DATA ARCHIVE ========================================== This document contains comments and errata concerning the Stardust SPICE Data Archive. 1. Text Kernel File Format -------------------------- All SPICE text kernel files (LSK, PCK, SCLK, IK, FK) provided on these volumes have lines terminated by only (UNIX convention.) This is dictated by NAIF's archiving approach to include a consistent set of UNIX binary (IEEE architecture) and text ( only for end of line marker) kernels on the archive volumes. However, the format of the text kernels is specified in their associated labels as ASCII (INTERCHANGE_FORMAT = ASCII.) This is a violation of the PDS standard stating that lines in ASCII files must be delimited by the combination of . This line termination treatment is standard practice for SPICE volumes in the PDS. 2. Use of SPACECRAFT_NAME in the Labels --------------------------------------- PDS labels for SPICE kernels provided in this data set contain the deprecated keyword SPACECRAFT_NAME instead of the keyword INSTRUMENT_HOST_NAME. This is standard practice for SPICE volumes in the PDS and is dictated by NAIF's archiving approach to make SPICE archives for more recent missions consistent with SPICE archives for older missions, for which use of SPACECRAFT_NAME was legitimate. 3. Values of INSTRUMENT_NAME in the Labels ------------------------------------------ PDS labels for SPICE kernels provided in this data do not set the keyword INSTRUMENT_NAME to "SPICE KERNELS", that is the name of the instrument described by the instrument catalog file SPICE_INST.CAT provided in the data set. Instead this keyword is set to either "N/A" or the name(s) of the instrument(s) or structure(s), the geometric parameters of which a particular kernel file provides. While this error does prevent the individual data products from being associated with the "SPICE KERNELS" instrument, it does not affect usability of the SPICE data provided in this data set in any way because the SPICE toolkit does not use any information from the PDS label to access the data. The other side of this error is that the data set does not include instrument catalog files for the following instruments named in the INSTRUMENT_NAME keyword in the PDS labels: "DUST COLLECTOR" "NAVIGATION CAMERA" "STARDUST SPACECRAFT BUS" "DUST FLUX MONITOR INSTRUMENT" "SAMPLE RETURN CAPSULE" "HGA" "MGA" "LGA1" "LGA2" "LGA3" 4. Missing FILE_RECORDS Keyword in the Binary Kernel Labels ----------------------------------------------------------- All labels for binary SPICE kernels provided in this data set are missing the FILE_RECORDS keyword, which is required because these labels have the RECORD_TYPE keyword set to FIXED_LENGTH. While this error violates the PDS standards, it does not affect usability of the SPICE data provided in this data set in any way because the SPICE toolkit does not use any information from the PDS labels to access the data. 5. Incorrect SCLK Values in the Comment Area of CK Files -------------------------------------------------------- The values of the SPACECRAFT_CLOCK_START_COUNT and/or SPACECRAFT_CLOCK_STOP_COUNT keywords in the copy of the PDS label embedded at the top of the comment area of CK files are incorrect for all CK files that contain more than one segment. The values of these keywords provided in the detached PDS labels are correct.