Cartography of the Icy Saturnian Satellites

Abstract

We have re-measured control points and re-computed a control point network for Saturn's satellite Dione. Our network is based on 16 images (obtained by the narrow-angle cameras of Voyager I and II), 135 control points, and 741 point measurements. We obtained mean point accuracies of 1.8 km, 2.9 km and 1.2 km for X, Y and Z, respectively. The radius of Dione was re-determined to be 562.5 km +/- 0.2 km with a RMS deviation of 3 km, consistent with 560 km (RMS: 5 km) found by Davies et al. 1983. Subsequently, we generated a sequence of controlled digital base mosaics for the five (among the largest) satellites Mimas, Enceladus, Tethys, Dione, and Rhea. The images are reprojected in Mercator and Polar Stereographic projections using satellite shape parameters, as recommendes by IAU. On the basis of these mosaics, maps in printable format have been produced. Our data products update previous control point networks and maps of these satellites, released by the RAND Corporation and The USGS (United States Geological Survey), respectively, between 1982 and 1992. Our maps constitute an important basis for the planning of the Cassini mission, which will begin its orbtial tour through the Saturnian system in June 2004 (http://saturn.jpl.nasa.gov).