This event is chosen to study the mapping of particle, wave, field and emission boundaries from POLAR to the Halley SuperDARN radar Field of View for a nightside period when Bz is strongly positive. POLAR has its perigee in the south with the ground track traversing equatorward to poleward through the radar FOV from 2330UT to 2355 on 28 May. The radar records a stable backscatter feature with a distinct boundary picked out in the spectral width. This boundary is associated with boundaries in waves, particles and E on POLAR. The backscatter region overlaps the region of luminosity observed by VIS field camera. Later (around 03 to 04UT on 29 May) there is a sharp step in the Scatter boundary in the noon midnight plane - possibly associated with BX,By changes. This latter period shows how the nightside is reconfiguring whilst POLAR is flying through the reconnection region on the northern dayside.