Aurora Report

[anonymous]

Hello there,

Having been a night sky watcher for much of my 45 years, and having witnessed numerous aurora events, I would like to report to you an aurora witnessed at 11:30  pm on Tuesday 27th July in the skys south/southeast of Wynyard in north west Tasmania.  This was by a very long way the most spectacular aurora I have seen.

Low in the southern sky was darkness, then at about 15 degree elevation was a relatively stable and narrow band of white light, much like the fringe of a shawl surrounding the darkest section close to the southern horizon.  Above this, and extending to around 50 degree elevation were irregularly changing searchlight effects, with what appeared to be beams of light projecting upwards from the 'shawl' into the night sky.  These were white coloured - not with the range of colours sometimes seen - and would come and go over a period of maybe 30 seconds to one minute.  Typically there would be five or so spotlight effects in the sky at the one time.

All of the above is pretty standard with regard to Auroras I have previously witnessed in this part of Tasmania.  What was different - and to my mind quite exciting - was an additional layer of aurora activity, consisting of horizontal bands of light, a little like cloud bands,  rising rapidly above the shawl effect to an elevation of around 75 degrees or perhaps slightly more, in a matter of two or three seconds.  A bit like waves coming onto a beach, these bands of light repeatedly and rapidly washed up and over the southern night sky, and the whole southern sky appeared to be pulsing rapidly.  The previously described spotlight effects were a backdrop to this display.

The whole display was the brightest aurora I have witnessed, being clearly visible from inside my car as I drove westward with high beams on, even though the moon was about half full.  I stopped and watched the display for about 15 minutes, and then resumed my drive westwards for a further 20 minutes.  On arriving home, at the coastline, I again watched the display for a further 45 minutes, with all aspects of the display repeated, though with about half the brightness of that previously witnessed.

Last night, when again the skys were very clear, I surveyed the southern skys between 9pm and 1 am, but did not observe any aurora activity.

I would be interested to hear any comments you may have about these observations, in particular about the horizontal bands that pulsed in the southern sky.

Greg Taylor
Cradle Coast NRM Facilitator 
Western Region
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