GEOMETRY OF SATURN MAGNETOPAUSE MODEL

We report on an idealized three-dimensional model of Saturn's magnetop ause. Using the subsolar point distance R(0) = 24 R(A), we provide an analytical parameterization of the magnetopause model described by Mau rice and Engle [1995]. This representation of Saturn's magnetopause is consistent with Voyager 1 magnetopause crossing observations. The mag netopause shape is then scaled to 17 R(A) less than or equal to R(0) l ess than or equal to 45 R(S) and applied to Pioneer 11 and Voyager 2 o bservations. Results highlight variations of R(0) during magnetopause crossings (over a few hours) and/or between inbound and outbound cross ings (over a few days). Finally, we extend the parameterization of Sat urn's magnetopause to nonzero dipole tilt angles. The model is intende d for use in support of the Cassini mission.