Median-averaged global ME expansion from the UVS reference oval in the day-side hemisphere vs. in the night-side hemisphere for perijoves 1 through 54, for the northern (red crosses) and southern (blue triangles) aurorae. The fitted relationships are given by a red dashed line and a blue dot-dashed line for the northern and southern hemisphere respectively; their forms and R-squared goodness-of-fit values are given in the legend. The 1σ confidence levels of the fits are given by the red and blue shaded regions, for the northern and southern hemispheres respectively. The position of the origin is denoted by two dotted black lines. Negative values of ME expansion indicate a global contraction of the ME.