GLOBAL OBSERVATION OF PROTON AURORAS BY IMAGE
19:56 Pre-substorm situation: faint single arcs are co-located in WIC and SI-12.
20:04 Sudden brightening in the electron aurora (WIC) near mid-night at about the same latitude as the proton aurora showing that the onset occurs in a region where there is significant proton precipitation.
20:15 Brightening (WIC) propagates towards dawn (to the left) and poleward with proton aurora (SI-12) expanding poleward.
20:23 Brighter surge in (WIC) is considerably more poleward than the bulk of the protons which reach peak brightness at this time.
20:31 Bright poleward arc (WIC) while protons fade at high latitude
20:47 Post substorm protons re-formed at low latitudes while the electron aurora has propagated poleward and dawnward.