Global simulations of Neptune’s magnetosphere using the Gorgon MHD code
Magnetic fields of planets and cool stars
L Mejnertsen
Imperial College London
J. P. Eastwood, J. P. Chittenden, A. Masters
Relatively little is known about the ice giant planet Neptune, as the Voyager 2 flyby in 1989 is the only in-situ measurement of the planetary system to date. Many important aspects of Neptune are still poorly understood, including basic questions concerning its formation, interior, atmosphere, and magnetic environment. With a highly tilted magnetic dipole and rotation axis, its magnetosphere is thought to be highly variable due to large daily and seasonal variations. Consequently, a deeper understanding of Neptune and its interaction with the solar wind could provide major insights into a variety of solar system science fields, as well as useful data for exoplanet research where many ice giants have been discovered.
To better understand the structure and dynamics of Neptune’s magnetosphere, computer simulations can play an important role. Adapting the existing MHD code, Gorgon, to the Neptunian system, we have performed new global simulations to model and explore the dynamics of Neptune’s magnetosphere. Unlike global simulations of other planets, such as Earth and Jupiter, a rotating dipole is simulated in real time.
We present initial work regarding the qualitative workings of Neptune’s magnetosphere and its interaction with the solar wind. By including the effects of Neptune’s daily rotation, the varying structure of the magnetosphere could allow solar wind entry through reconnection, as well as creating imbalances in the inner magnetospheric density between the North and South lobes, leading to a highly dynamic and asymmetric magnetosphere. The results are examined in the context of data measured by Voyager 2.


09:00 - 10:30