The Archiving Process

Refer to the Archive Preparation Guide for details of the archiving process.

The PDS archives and distributes documented data to the planetary science community. It was established in response to requests for increased availability of planetary data and to concerns that data from past NASA missions were degrading to the point of becoming unusable for analysis. PDS functions include both ingestion and distribution of data at 'nodes' specializing in certain scientific disciplines and/or technical skills. A central catalog provides high level information on node holdings. More information about the archive lifecycle.

In order to fulfill its charter, the PDS requires that data it handles be understandable, be in formats that future scientists will find easy to use, and follow standards for organization and content that facilitate collaboration across missions and science disciplines. The PDS requires that submitted data meet published standards regarding format, content, and documentation. A range of formats has been defined, but 'tables' and 'images' account for the majority of products. Data products are organized logically into 'data sets,' which are sometimes organized into 'data set collections'. Data may be written to 'volumes' and 'volume sets' on physical media such as CD-ROMs and DVDs. More information about acceptable archive formats is in the Mission Proposer's Archiving Guide (MPAG) (PDF).

At an early stage mission and instrument personnel should define the data products they intend to archive, estimate their volume and generation rate, and negotiate a preliminary delivery procedure with the PDS. Adequate documentation for both understanding and using the data is critical to each archive; mission planners should be mindful of the archive documentation requirement as they develop explanatory materials for other purposes. All archive submissions to the PDS are peer-reviewed by scientists and data engineers to ensure that PDS standards have been met and that the archive is complete and the data are useful. This usually occurs at several stages for mission archiving.

Once data are fully integrated into the PDS, they may be retrieved through electronic queries over the internet, or by special request on physical media such as CD-ROM. The PDS provides copies of all accepted data sets to the National Space Science Data Center (NSSDC), which serves as both the PDS 'deep archive' and the official distribution point for requests originating outside the planetary research community.