The Outer Magnetosphere of Saturn during Cassini Orbit Insertion

ACHILLEOS, N.; BERTUCCI, C.; DOUGHERTY, M. K.; BURTON, M.; CASSINI MAGNETOMETER

Congreso; American Astronomical Society, DPS meeting #36,; 2004

During the time of Cassini orbit insertion around Saturn (SOI), the magnetometer instrument (MAG) detected a wide variety of magnetic signatures, each associated with distinct regions of the planet's magnetosphere. In this presentation, we concentrate on the time intervals when Cassini was in the outer regions of Saturn's magnetosphere (>10 RS) and close to its boundary, the magnetopause. Magnetic signatures include: the field generated by Saturn's plasma sheet; the 'quiet' field region of the magnetospheric lobes; and the crossings of the magnetopause by the spacecraft. The geometry of these crossings indicates that Saturn's magnetosphere was in a compressed state during the outbound pass, as compared to the inbound interval. We apply an empirical magnetopause model to the data, in order to estimate the corresponding changes in solar wind pressure and magnetospheric size.