Size and Shape of Saturn's Moon Titan
Publication date: 16 May 2009
Authors: Zebker, H.A. et al.
Cassini observations show that Saturn's moon Titan is slightly oblate. A fourth-order spherical harmonic expansion yields north polar, south polar, and mean equatorial radii of 2574.32 +- 0.05 kilometers (km), 2574.36 +- 0.03 km, and 2574.91 +- 0.11 km, respectively; its mean radius is 2574.73 +- 0.09 km. Titan's shape approximates a hydrostatic, synchronously rotating triaxial ellipsoid but is best fit by such a body orbiting closer to Saturn than Titan presently does. Titan's lack of high relief implies that most-but not all-of the surface features observed with the Cassini imaging subsystem and synthetic aperture radar are uncorrelated with topography and elevation. Titan's depressed polar radii suggest that a constant geopotential hydrocarbon table could explain the confinement of the hydrocarbon lakes to high latitudes.Link to publication