The Data directory is divided into 4 sub-directories, each containing DATA files for a different PVO ORPA component. The 4 components include: 1) Reduced thermal electron mode sweeps, 2) Reduced ion mode sweeps (which contains uncertainties), 3) Reduced photoelectron mode sweeps, and 4) Low Resolution (UADS) data (density, temperature, S/C potential). The sub-directories are further divided to create groups of 100 orbit files per directory. Catalog information (metadata) associated with this data archive are located in the /CATALOG/*.CAT files. The original documents describing the structure of the data files, the instrument, and other related papers are reproduced in ASCII form as *.ASC files, in the /DOCUMENT directory. The /DOCUMENT directory also contains the scanned image "GIF89A" files which contain useful graphics describing the various instruments, as well as full representations available in an HTML document. In each of the data directories as part of the PDS label, ".FMT" files exist explaining the structure of the data files as described by the original document. STRUCTURE | |- DATA | |- ION |-ORB0001 |-DATA |-UNCERT |-ORB0101 |-DATA |-UNCERT ... |-ORB0801 |-DATA |-UNCERT |-ORB0901 |-DATA |-UNCERT | |- LOW_RES | |-ORB0001 |-ORB0101 ... |-ORB0801 |-ORB0901 | |- PHOTOELE | |-ORB0001 |-ORB0101 ... |-ORB0801 |-ORB0901 | |- THRM_ELE | |-ORB0001 |-ORB0101 ... |-ORB0801 |-ORB0901