Archiving CDF in PDS4: A MAVEN Case Study

NASA's Common Data Format (CDF) is widely used by NASA Heliophysics Division missions and for data obtained from ground based observatories. It has begun to be used in the Planetary Division by the ARTEMIS and MAVEN missions, as well as by a number of international missions. As NASA planetary missions are required to archive data with the Planetary Data System (PDS) there was a desire that PDS begin to accept CDF formatted data into the archive. While this was difficult under the PDS3 Information Model (IM), the new PDS4 IM is flexible enough to allow properly constrained CDF formatted data to be described by using PDS4 metadata. The approach taken has been to capture as much of the CDF metadata in the PDS metadata as possible, while describing both the physical and logical data structures by using a combination of the PDS4 common data dictionary and a series of local data dictionaries. This method has been realized in the PDS MAVEN archive. There is also an ongoing effort to archive Cassini high order data in CDF.