  The datum of Digital Elevation Model of North Pole of Venus, provided there, derived from
raster data of Global Topography Data Record of Magellan mission, which distributed by 
Planetary Data System (PDS) of NASA. Base resolution of the datum is about 4641m. 
The data uses Polar Stereographic Projection with true scale latitude of 90°.
  The datum presented here generally in form of .ZRS-files (stands Zipped Raster Set),
which is proprietary compressed format of author of the datum. Separated files of the datum
are in hierarchical and multi-resolution relation for optimization of speed and appearance 
upon using in Spatial Aspect Viewer and Spatial Aspect Explorer software products of author.
  Also the datum contents set of spatial regions covering main features of North Pole of Venus.

See site of author: www.runspect.com for more details.
Copyright (c) 2011-2016 Yuri Feldman
