Observations of the jovian system in the near-infrared (3.4 mu m) reveal a
wealth of information about Jupiter's magnetic field, magnetosphere, and ma
gnetospheric dynamics. This wavelength contains a few emission lines of the
H-3(+) ion and it is centred on a deep methane absorption hand. As a resul
t, one can image Jupiter's ionosphere at this wavelength with extraordinary
signal-to-noise ratio, against a planet otherwise darkened by absorption d
ue to methane in its atmosphere. High spatial resolution images of the plan
et's surface provide a synoptic view of the entire magnetosphere, fr-om the
electrodynamics of Io and the torus, to the excitation of auroral displays
at high magnetic latitude. Observations of the Io Flux Tube footprint have
provided a new magnetic coordinate system for the jovian polar regions and
new insight into the electrodynamic interaction between Jupiter and Io. Sh
ort-term temporal variations (days) of auroral intensity are observed in th
e IR and are well correlated with variations in the solar-wind ram pressure
arriving at Jupiter. These H-3(+) emissions are thermally excited and are
a good proxy for time-averaged energy deposition. It is now possible to pro
duce detailed maps of energy deposition from the Io footprint (L = 6) to th
e pole, in which both system III and local time variations are evident.