Black aurora - last update: 18 February 1997, 1100 UT (RR)
Black aurora is a lack of auroral emission in a small, well-defined region within an otherwise uniform, diffuse background or within auroras exhibiting a degree of shear behaviour intermediate between that of diffuse and discrete aurora (e.g., Davis, 1978). It appears to be a common feature of the midnight sector during late substorm recovery phase (Trondsen and Cogger, 1997).


See also: