![]() Khurana derived a current sheet model from the magnetic field data obtained by Voyager 2. This waveform is the result of a current sheet crossing caused by the tilt of the Jovian dipole moment to the spin axis. The most prominent perturbation is a rectangular magnetic field waveform with a 10-hour period. In the Jovian magnetosphere, the magnetic field has been observed by the Pioneer 10 and 11, Voyager 1 and 2, Ulysses, Galileo, and Cassini missions. Magnetic field measurements have been the most important and fundamental technique required for the investigation of the electromagnetic environment of planetary magnetospheres since the beginning of space research. We suggest that the current sheet is greatly deformed and reconnection bursts are induced under the compressed magnetosphere. The maximum amplitude of the disturbances is in proportional to the maximum amplitude of the solar wind dynamic pressure. Magnetic field disturbances in the frequency range from 0.3 to 10 mHz are enhanced simultaneously. The rectangular waveform due to the Jovian rotation disappears for eight of the nine events. Characteristic magnetic field variations are found in the Jovian magnetosphere for all of the nine events. We identify the events with an increase of the solar wind dynamic pressure >0.25 nPa at the Jovian orbit. The lack of solar wind monitoring just upstream of the Jovian magnetosphere is overcome by simulating a one-dimensional magnetohydrodynamic (MHD) propagation of the solar wind from the Earth. ![]() The model uses the 81-day average value of the F10.7 solar flux, 20 months prior to the given date, to track changes in the ring current base line with solar cycle progression (F10.7 default value is 120.0).In order to understand the response of the Jovian magnetosphere to solar wind dynamic pressure enhancements, we investigate magnetic field variations observed by the Galileo spacecraft. A default value of 0.5 mV/m is to be used if the value of Em is not known. The merging electric field Em is a parameter derived from the solar wind measurements by: Em (in mV/m) = V * BT * sin(beta/2.0) * sin(beta/2.0) / 1000, where V is the solar wind flow speed in km/s, BT is the strength of the interplanetary magnetic field perpendicular to the Sun-Earth axis and beta is the clock angle acos(Bz/BT). The Interplanetary magnetic field and F10.7 index are available from OMNIWEB (default IMF-BY = 0.0). The magnetospheric ring current is tracked by Est/Ist (the default values for Est and Ist are both 0.0). The model is more accurate if the present state of the magnetosphere is provided as an input in the form of magnetic indices. The transforms from GSM and SM coordinates to GEO coordinates were last updated for POMME-9. It has the same parametrization of the magnetospheric field as POMME-6, POMME-7, POMME-8 and POMME-9. ![]() Pomme-10 was produced from CHAMP satellite vector magnetic measurements from July 2000 up to September 2010, Oersted satellite total field measurements from January 2010 to June 2014 and Swarm satellite vector magnetic measurements from December 2013 to November 2015. The time variations of the internal field are given by a piece-wise linear representation of the spherical harmonic (Gauss) coefficients of the magnetic potential. POMME is a scientific main field model representing the geomagnetic field in the region from the Earth's surface to an altitude of a couple of thousand kilometers. ![]()
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