Producing a PDS Archive

Design

1. Organize the expected data into DATA SETS. Include:
   • Raw data
   • Calibrated data
   • High-level products (image mosaics, e.g.)
   • In-flight calibration observations
   • Calibration files
   • Ancillary data (attitude, pointing, shape models, etc)

2. Decide how to divide the data among the publication VOLUMEs.

3. Define the names and IDs to be used throughout the archive:
   • DATA_SET_ID — DATA_SET_NAME
   • INSTRUMENT_ID — INSTRUMENT_NAME
   • INSTRUMENT_HOST_ID — INSTRUMENT_HOST_NAME
   • MISSION_NAME
   • TARGET_NAME, for both major mission targets and calibration targets

4. Define the archive data file structures.
   • Strive for simple, regular record formats
   • Avoid compressed and proprietary formats

5. Design the labels for all data files.
   • Labels may be attached or detached
   • Label keywords provide several types of information. For example, the required keyword set for space data:

     File Charcteristics

     • PDS_VERSION_ID
     • RECORD_TYPE
     • RECORD_BYTES
     • FILE_RECORDS

     Catalog Information

     • DATA_SET_ID
     • PRODUCT_ID

     Search Parameters

     • SPACECRAFT_NAME
     • INSTRUMENT_NAME
     • TARGET_NAME
     • START_TIME
     • STOP_TIME
     • SPACECRAFT_CLOCK_START_COUNT
     • SPACECRAFT_CLOCK_STOP_COUNT

   • Select an OBJECT appropriate to data structure:
     • IMAGE for raster images
     • SPECTRUM for linear spectra
     • TABLE for ASCII or binary tabular data
     • SPICE for NAIF kernels
     • QUBE for ISIS spectral cubes
     • Consult PDS for more complex file structures

   • Select additional descriptive keywords as desired from the Planetary Science Data Dictionary.

Assembling the Archive

1. Collect and prepare the documentation. Typical documentation includes:
   • Mission overview, timeline, summary, etc.
   • Spacecraft descriptions
   • Instrument descriptions
   • Calibration papers
   • Data set descriptions
   • Observation logs
   • User's manual

   Preparation consists of:

   • Obtaining copyright permission for reprints
   • Generating the ASCII formats as needed
   • Creating the labels

2. Create the catalog files. PDS can supply templates and examples for all required files:
   • MISSION
   • INSTRUMENT_HOST - i.e., the spacecraft
   • INSTRUMENT - one for each instrument
   • DATA_SET - one for each unique DATA_SET_ID
   • REFERENCE - a REFERENCE template is filled out for each reference cited anywhere in the documentation or other catalog files. All the completed REFERENCE objects are collected into a single file in the CATALOG directory.

3. Collect and prepare any additional materials to be included:
   • Software, depending on its purpose in the archive:
     • Label as SOFTWARE and store in the SOFTWARE directory only if there is long-term commitment to support and port the software as needed.
     • Label as DOCUMENT and store in the DOCUMENT directory if the code is being supplied as supplementary documentation of algorithms or procedures described elsewhere.
     • Store in EXTRAS directory (no labels required) if the software is a contemporary convenience which does not substantially contribute to the archive.
   • Web Sites - consult PDS engineer for labelling and placement in the volume structure
   • Consult PDS engineer for placement of other materials.

4. Create the file labels. Every file that is part of the permanent archive must have a label to support identification and retrieval.

Creating the Volumes

1. Move the assembled information into the corresponding directories. These may be further subdivided as needed or desired. Note that detached label files reside in the same directories as their data files:

   /DATA

   All mission data files

   /CALIB

   All calibration files and in-flight observations

   /GEOMETRY

   All attitude and pointing data, include SPICE kernels (if any)

   /DOCUMENT

   All documentation files and graphics

   /INDEX

   All indices

   /CATALOG

   All PDS catalog files except for "VOLDESC.CAT"

   Note that sometimes entire directories are copied verbatim on each volume in a series. This is nearly always true for the /CATALOG directory, and is frequently true for the /DOCUMENT directory.

2. Create the indices in the /INDEX directory.
   • For archiving purposes, PDS requires a volume index of a fairly specific form to act as a manifest of all data files on the volume. The specialized INDEX_TABLE object is used to label this file, called "INDEX.TAB".
   • When an archive is delivered as a series of volumes, PDS also requires a cumulative index, of the same form as "INDEX.TAB". This also uses the INDEX_TABLE object.
   • Additional indices may be included as desired. Use the standard TABLE object to label these indices.

3. Write the volume documentation files. The following files appear at the root level. A PDS data engineer can supply examples:
   • AAREADME.TXT provides an overview of the volumes, including a summary of volume directory structure and content. This file has a small, attached PDS label.
   • ERRATA.TXT lists errata known but not corrected as of press. If there are no errata, this is omitted. The file begins with a small, attached PDS label.
   • VOLDESC.CAT, the only PDS catalog file not found in the /CATALOG directory, provides cataloging information for the volume as a whole.

   In addition, each major subdirectory except /DATA also contains an INFO.TXT file. These files provide information about the contents and structure of the directory. They each begin with a small, attached PDS label and have a name prefix which corresponds to the directory. For the directories mentioned above:

   • DOCINFO.TXT resides in the /DOCUMENT directory.
   • CATINFO.TXT resides in the /CATALOG directory.
   • CALINFO.TXT resides in the /CALIB directory.
   • INDXINFO.TXT resides in the /INDEX directory.
   • GEOMINFO.TXT resides in the /GEOMETRY directory.