For purposes of indexing, BRO files are considered data and will appear in these files. The remaining directories at the root level contain data files and detached PDS labels. All data files on the disc are accompanied by detached PDS labels, which describe their contents. PDS TEXT objects have attached labels. The label fully describes the format and content of its associated file.
Some data files contain more than one structure.
The Goddard group has also provided a grid of gravity anomaly uncertainties. The JPL group has provided a grid of geoid height above a reference ellipsoid. All grids have one degree point spacing and use a simple cylindrical projection. The BRO directory contains PostScript representations of both gridded products from the Goddard group. These data were collected under auspices of the Mars Global Surveyor Project.