PDS_VERSION_ID                = PDS3
RECORD_TYPE                   = STREAM
OBJECT                        = TEXT
  PUBLICATION_DATE            = 2016-05-06
  NOTE                        = "Description of the CATALOG
     directory contents for the MESSENGER DEM Archive"
END_OBJECT                    = TEXT
END


                      MESSENGER Digital Elevation Model
                         CATALOG Directory Contents
                               March 30, 2016


The CATALOG directory contains information about the MESSENGER mission,
spacecraft (instrument host), Digital Elevation Model (DEM) data sets in this
archive.

The following files are found in this directory.

CATINFO.TXT        - The file you are reading.

MDIS_DEM_DS.CAT    - This file contains data set objects for Mercury Digital
                     Elevation Model (DEM). Files from this dataset are
                     present in the DEM directory.

DEM_EQU_MAP.CAT    - DEM data set map projection information for the
                     equatorial region. Simple cylindrical projections are a
                     special case of equirectangular projections. The products
                     in this volume identified as simple cylindrical reference
                     this file as well.

DEM_POLAR_MAP.CAT  - DEM data set map projection information for 
                     polar regions.

DEM_LMBRT_MAP.CAT  - DEM data set map projection information for lambert
                     conformal map projections.

MDIS_WAC_INST.CAT  - This file contains a description of the Wide 
                     Angle Camera (WAC) which is one of two framing 
                     cameras in the MDIS instrument and investigation.

MDIS_NAC_INST.CAT  - This file contains a description of the Narrow 
                     Angle Camera (NAC) which is one of two framing 
                     cameras in the MDIS instrument and investigation.

INSTHOST.CAT       - A description of the MESSENGER spacecraft
                     (instrument host) that carried the instrument.

MISSION.CAT        - A brief description of the MESSENGER mission.
                     It includes a chronology of events, definition
                     of mission phases, and science objectives.

PERSON.CAT         - A listing of key people involved in producing
                     this archive.

REF.CAT            - A listing of references cited in these catalog
                     files.