A team of physicists from the University of Iowa (USA) has identified a type of aurora unknown until now. It takes place when the diffuse aurora, a tiny glow that remains in the background after the most striking brightness of traditional auroras, it darkens and suddenly reappears to offer us all its splendor in the night sky.
In March 2002, physicist David Knudsen noticed something extraordinary while observing the auroras in northern Canada. After filming the aurora, the matter stayed there. Almost two decades later, the video they recorded at that time has been studied intensively and it turns out that the auroral phenomenon they saw in 2002 had not been recorded before.
Physicists still they don’t understand what caused this curious aurora or how often it takes place, but it is clear that now we are on the way to find out. It is unusual that this new and elusive type of aurora was observed in a 19-year-old video made by a physicist and that it had never been described in the scientific literature before.
The video, recorded on March 15, 2002 in Churchill, a city in northern Manitoba, Canada, on the west coast of Hudson Bay, was not seen by the eyes of the observers. Despite clear skies and a location reasonably close to Earth’s north geomagnetic pole, none saw it, but the camera did catch it. It was sensitive enough to capture the diffuse auroral background and dimming events.
“A diffuse, pulsating ‘dimming’ glow, which then fills in for several seconds,” Knundsen wrote in his notes.
The researchers ‘christened’ the phenomenon as “Fuzzy auroral drafts.”