Data Set Overview
      =================
      This data set contains the Philip Stooke shape models for small
      solar system bodies.  These shape models are based on optical data
      and are distinct from the shape models based on radar observations
      which are included in a separate data set,
      EAR-A-5-DDR-RADARSHAPE-MODELS-V1.0.  Other optical shape models
      prepared by Peter Thomas are also available in PDS data set
      EAR-A-5-DDR-SHAPE-MODELS-V2.1.
 
      The current version of this data set contains shape models for
      243 Ida, 951 Gaspra, comet Halley, J5 Amalthea, N7 Larissa,
      N8 Proteus, S10 Janus, S11 Epimetheus, S16 Prometheus, and
      S17 Pandora.
 
      Parameters
      ==========
      The shape models consist of a grid of body-centered latitude and
      longitude with a radius listed for each grid point.  Coordinates
      are planetocentric, increasing to the west.  West is defined as
      being to the left when north is up, regardless of the rotation
      direction of the body.  North is defined as the pole on the north
      side of the invariant plane of the solar system.  (These are the
      cartographic coordinate system definitions approved by the IAU's
      Working Group on Cartographic Coordinates, reported in Seidelman,
      et al. 2002) [SEIDELMANETAL2002].  Radii are given in kilometers.
 
      Uncertainties are highly variable from place to place, depending
      on locations of limb profiles used to create the models.  Thus,
      the data format cannot reflect the accuracy of the radii and there
      may be more decimal places given than are significant.  An
      estimate of uncertainties is provided in the data label where
      available.  A full discussion of the uncertainties of the models
      is available in the published papers.
 
      Further details are given in the relevant published papers.
 
      Seidelmann, P.K., Abalakin, V.K., Bursa, M., Davies, M.E., de
      Bergh, C., Lieske, J.H., Oberst, J., Simon, J.L., Standish, E.M.,
      Stooke, P.J. and P.C. Thomas.  'Report of the IAU/IAG Working
      Group on Cartographic Coordinates and Rotational Elements of the
      planets and satellites: 2000.'  Celestial Mechanics and Dynamical
      Astronomy, v. 82, 83-100, 2002. [SEIDELMANNETAL2002]

P. Stooke notes (especially with respect to the Comet Halley
      model):
 
         Comparison of independent shape models by P. Stooke and
         P. Thomas for the same bodies (Amalthea, Janus, Epimetheus)
         suggests that Thomas tends towards models more convex than
         the likely shapes, and Stooke tends towards models which
         are too faceted, or which exaggerate the depths of depressions.
 
      Review
      ======
      This data set underwent external peer review on May 10, 2002.