Definitions

The areocentric coordinate system is a right-handed system with the origin at the center of mass of Mars.  Areocentric latitude is the angle between the equatorial plane and a vector connecting a point on the surface and the origin of the coordinate system.  Latitudes are positive in the northern hemisphere and negative in the southern hemisphere.  Areocentric longitude increases to the east.

See here for a complete discussion of coordinate systems used in ODE.

A data product is a set of measurements resulting from a science observation, usually stored in one file.  For example, an image, a spectrum, and a time series table of measurements are data products.  A data product has a PDS label that contains metadata about a product such as when and where the data were collected, what the data contain, and as how the data are organized.  These labels are either detached files or attached at the beginning of a data product file.  More information about data products can be found in the PDS documentation here.

Planetary science data stored in PDS are organized by data sets.  A data set is a collection of related data products, usually data products acquired by a particular instrument and processed in a certain way.  Each data product within a data set is of a given product type and has a unique Product ID.  The data set also includes all documentation and supporting materials needed to understand and use the data products.  Data sets are stored in volumes.  For example, most MRO data sets are stored in a single volume.

The term derived files (or in some cases, derived products) refer to products or files derived from other PDS science products.  In some cases, these are generated by the instrument teams and included in the PDS Archives.  An example is the Derived Data Records (DDRs) of the CRISM instrument.  ODE itself also generates derived files to improve PDS usability. For example, product coverage footprint files.

Each data product has a “Product ID”.  The Product ID is a permanent, unique identifier assigned to a data product by its producer.  The Product ID is unique within a data set.  The Product ID is a character string up to 40 characters in length.  Many producers embed information about the product in the Product ID.  For example, the Product IDs of HiRISE data products include both the mission phase and the orbit number in which the data product was generated.

Each data product is of a single “Product Type”.  A product type identifies the type or category of a data product within a data set.  For example, raw observation data products usually have a product type of “Experimental Data Record” or EDR for short.  Other examples include “Reduced Data Record” (RDR for short), DOCUMENT, CALIBRATION, ANCILLARY, or VALIDATION_REPORT.

NASA’s Planetary Data System (PDS) Geosciences Node’s Orbital Data Explorer (ODE) provides map and forms-based search, retrieve, and order function for PDS-compliant archives from a variety of spacecraft instrument observations.  Mars ODE includes observations from Mars Reconnaissance Orbiter (MRO), the European Space Agency’s Mars Express (MEX), Mars Odyssey, the Mars Global Surveyor (MGS), and the Viking Orbiter (VO) spacecraft.  The MRO mission is characterized by very high data volumes and complex observation plans relative to previous planetary missions.   Mercury ODE includes observations from the MESSENGER (Mercury Surface, Space Environment, Geochemistry and Ranging) spacecraft.  Lunar ODE  includes observations from the Clementine, Lunar Prospector, the Lunar Reconnaissance Orbiter (LRO), and ISRO's Chandrayaan-1, and Lunar Orbiter (LO) spacecraft .  Venus ODE includes data from the Magallen and MESSENGER spacecraft.  ODE is designed to augment the existing PDS search and retrieval interface by providing advanced search, retrieve, and order tools, integrated analysis tools, and visualization tools.  

NASA’s Planetary Data System (PDS) archives and distributes scientific data from NASA planetary missions, astronomical observations, and laboratory measurements. The PDS is sponsored by NASA's Science Mission Directorate. Its purpose is to ensure the long-term usability of NASA data and to stimulate advanced research. PDS is continually upgrading and updating its archives, to better serve the needs of its user communities.