The Starbase One Astronomy & Space Collection/STARBASE_ONE.ISO/images/planets/saturn/janusm.txt

Text File | 1995-02-02 | 1.6 KB | 37 lines

SHADED RELIEF MAP OF JANUS

Janus.gif is a shaded relief map of Janus, the larger co-orbital
satellite of Saturn.  As with all maps, it is the cartographer's
interpretation and not all features are necessarily certain given the
limited data available - this interpretation stretches the data as far
as is feasible.  The original map was published in its full form with
latitude-longitude grid, in:

Stooke, P.J. and Lumsdon, M.P., 1993.  "The Topography of Janus",
    EARTH, MOON AND PLANETS, V. 62, pp. 223-237.

Positions in the map are controlled by a digital shape model, described
in that paper.  For this map, the three dimensional convex hull of the
shape model was projected into the Morphographic Conformal Projection
(the conventional Stereographic Projection modified for non-spherical
worlds).  The leading side (longitude 90 runs vertically down the centre)
faces forwards in the orbit of Janus.  The trailing side (longitude
270 runs vertically down its centre) faces backwards along the orbit.
Longitude 0 is at the righthand end of the leading side, and faces Saturn.
As with all conformal (true shape) projections, the scale in these maps
varies, increasing from the centre to the outer edge.

The map projection is described in:

Stooke, P.J. and Keller, C.P., 1990.  "Map Projections for Non-Spherical
Worlds / the Variable-Radius Map Projections", CARTOGRAPHICA, V. 27, No.
2, pp. 82-100.

This version of the file, with labels intact, is in the public domain.

Philip Stooke,
Department of Geography,
University of Western Ontario,
London, Ontario, Canada N6A 5C2
[e-mail]