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.
All grids have one degree point spacing and use a simple cylindrical projection.
There are three files from the surface reflection investigation. These are intended as examples of larger numbers of files to be produced later. File 9133H43A.SRT in the SRT directory is a tabulation of results from analysis of the echo signal properties, including strength, frequency drift, etc. Each file is accompanied by a full PDS label describing the format and contents. These data were collected under auspices of the Mars Global Surveyor Project.