Data within the PDS is organized as data sets, which are collections of data observations or products, and associated supplementary files that document and support the use of the data.
A data set usually includes the following components:
- Data products and labels
- Labeled groupings of data resulting from a scientific observation. Labels that provide a field-by-field description of the contents of the associated file accompany PDS data product files. In general each data file has its own label; a single label may be used to reference several distinct files in cases where those files are closely related (chapters of a document, for example). Labels may be attached (stored as part of the data file) or detached (the label is a standalone file with pointers to the associated data product).
- Textual material which describes the mission, spacecraft, instrument, and data set. This can include references to science papers, calibration reports, and other text useful for interpreting the data.
- Catalog Files
- Files containing descriptive information about a data set (e.g., mission description, instrument host description, instrument description).
- Software libraries, utilities, or application programs to access/process the data products.
- Calibration data
- Calibration files used in the processing of the raw data or needed to use the data.
- Geometry data
- Relevant files (e.g., SEDRs, SPICE kernels) needed to describe the observation geometry.
- Information that allows the user to locate the data products of interest, such as a table relating latitude/longitude ranges to file names.
Data sets themselves may be organized into data set collections that consist of data sets that are related by observation type, discipline, target, or time, for a specific scientific purpose.