Supporting materials and data from: Hypotheses concerning global magnetospheric convection, magnetosphere-Ionosphere coupling, and auroral activity at Uranus

Summary: The data and figures contained in this dataset are
supporting materials for the paper referenced in the title and abstract
below.  This study involved an analytical and numerical
assessment of the Uranian magnetosphere and its interaction with the solar
wind and interplanetary magnetic field (IMF). The data and figures
contained in this dataset include supplementary results for a greater
number of IMF orientations and Uranian seasons than the examples presented
in the corresponding paper. Abstract from corresponding paper:
doi:10.1029/2023JA031791 with Journal of Geophysical Research Space
Physics:We investigate the unique magnetosphere of Uranus and its
interaction with the solar wind. Following previous work, we developed and
validated a simple yet valuable and illustrative model of Uranus’ offset,
tilted, and rapidly-spinning magnetic field and magnetopause (nominal and
fit to the Voyager-2 inbound crossing point) in three-dimensional space.
With this model, we investigated details of the seasonal and
interplanetary magnetic field (IMF) orientation dependencies of dayside
and flank reconnection along the Uranian magnetopause. We found that
anti-parallel (magnetic field shear angle greater than 170-degrees)
reconnection occurs nearly continuously along the Uranian dayside and/or
flank magnetopause under all seasons of the 84 (Earth) year Uranian orbit
and the most likely IMF orientations. Such active and continuous driving
of the Uranian magnetosphere should result in constant loading and
unloading of the Uranian magnetotail, which may be further complicated and
destabilized by sudden changes in the IMF orientation and solar wind
conditions plus the reconfigurations from the rotation of Uranus itself.
We demonstrate that unlike the other magnetospheric systems that are
Dungey-cycle driven (i.e., Mercury and Earth) or rotationally driven
(Jupiter and Saturn), global magnetospheric convection of plasma, magnetic
flux, and energy flow may occur via three distinct cycles, two of which
are unique to Uranus (and possibly also Neptune). Our simple model is also
used to map signatures of dayside and flank reconnection down to the
Uranian ionosphere, as a function of planetary latitude and longitude.
Such mapping demonstrates that “spot”-like auroral features should be very
common on the Uranian dayside, consistent with observations from Hubble
Space Telescope. We further detail how the combination of Uranus’ rapid
rotation and unique and very active global magnetospheric convection
should be consistent with fueling of the surprisingly intense trapped
radiation environment observed by Voyager-2 during its single flyby.
Summarizing, Uranus is a very special magnetosphere that offers new
insights on the nature, complexity, and diversity of planetary
magnetospheric systems and the acceleration of particles in space plasmas,
which might have important analogs to exoplanetary magnetospheric systems.
Our hypotheses can be tested with further work involving more advanced
models, new auroral observations, and unprecedented missions to explore
the in situ environment from orbit around Uranus, which should include a
complement of magnetospheric instruments in the payload.