During substorms, auroral forms called omega-bands (named for their appearance) occur. A case study of omega-band structures with a well-positioned satellite constellation was performed and concluded that omega-bands map deep in the inner magnetosphere. This finding refuted earlier claims of their mapping to the outer magnetospheric boundary.
To address global aspects of the inner magnetosphere during magnetic storms, statistical analyses of large data sets were performed. Models of the particle and magnetic field environment were constructed to explore large-scale spatial distribution and evolution with geomagnetic state. These models revealed the complex behavior of the ring current during storms, including azimuthal asymmetries and systematic motions of the eastward-flowing and westward-flowing ring currents.
Novel energetic neutral atom (ENA) imaging techniques were used to construct the first global instantaneous snapshots of the Earth's magnetosphere. ENAs are emitted from the inner magnetosphere in a charge-exchange reaction between hot ions and the Earth's extended neutral atmosphere. Analysis of these images revealed that average pictures are correct to first order, but there is more complexity in space and time. The global evolution of the ring current was followed in time and a simple theory constructed to demonstrate the relationship between ENA production and ring current intensity. An earlier theory relating these parameters was generalized. The ENA images were used also to study the onset location and timing of substorm injections. This study produced the first instantaneous images of magnetospheric substorms. Simple three-dimensional models of ENA production were constructed to guide physical understanding of the ENA images.