On the plasma conditions at the dayside magnetopause of Saturn

The energy densities ϵ P of the low energy ions measured by the Low Energy Charged Particle (LECP) experiment on Voyager 1 and 2 are compared to the magnetic field energy densities derived from the magnetometer (MAG) instrument during the crossing of the dayside Saturn magnetopause. The ratios of the proton to magnetic field energy densities are ≳0.5 during the Voyager 2 crossing when the magnetopause was at ∼18 R S . During the Voyager 1 crossing of the magnetopause at ∼23 R S , the ratios were ∼0.1, although they approached one as the spacecraft entered the region near 18 R S . The observations show that the dayside Saturnian magnetopause can at times have high beta plasma conditions, similar to the situation found at Jupiter.