Fig. 3From: Post-midnight purple arc and patches appeared on the high latitude part of the auroral oval: Dawnside counterpart of STEVE?Projection of the DNB image and all-sky image to 100 km altitude. Both the purple and green arcs extended east–west widely. White arrows guide the continuity of the purple arc in the DNB image. Blue and yellow arrows indicate the trajectories of Swarm A and B, respectively. White grid lines show the AACGM latitude and local timeBack to article page