A little about the background for the display: The magnetosphere was recovering from a severe geomagnetic storm that had included 9 hours with KP = 9 (the highest activity level, aurora visible in central US and Europe), but a few hours before this display a new shock had arrived and now pushed the activity back up to major storm levels (KP = 6-7). In the previous photos it appears as if the auroral oval expands and moves south. In the following photos almost all the aurora is on the southern horizon, and red aurora at high altitudes (typically 200-500km vs. 90-150km for the green) becomes visible. Red auroras are only visible during strong geomagnetic disturbances and especially in connection with the onset of these (at least as seen here from Alaska). This is the first time I've managed to capture it, but then I've only had my camera for 10 months. This was not a strong red aurora and only barely visible to the naked eye. The 'Great Red Auroras' occur only at the onset of the largest geomagnetic storms and are pure red (no green). We should have had a couple of those too, but as mentioned Fairbanks has been shrouded in clouds. Very frustrating. :-)

Aurora gone south and red III

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