Montana Aurora Report (a serious report - this time)

I had seen Sam Wormley's postings and was aware of the possibility of
auroral activity on Sunday night (Nov. 7th) and Monday morning (Nov.
8th, 2004).

My first sighting of auroral activity was made quite by accident when
I went to the kitchen for something to eat or drink. The bright,
colorful, aquamarine glow visible through the window on my northern
horizon was unmistakable. I knew immediately that a bright aurora was
in progress. This was early in the evening on Sunday. We
extinguished most interior lights and spent some time going out and
in.

Some relevant details concerning my location: I live in rural Montana
at a latitude greater than 45 degrees North. Naked Eye Limiting
Magnitude tends to be 6.0 or better as soon as I step outside. I have
a few line-of-sight neighbors; but the nearest, like myself, has no
outside security lighting. The only other neighbor not at least
partially blocked from view by pine trees has been keeping his (two of
them!) security lights off most of the time. Sunday night was no
exception. For auroral observing purposes I could view a dark sky
around 360 degrees of azimuth.

Quite a few clouds were in the sky initially; but as time passed my
sky became almost completely clear and highly transparent.

For the most part color (such as green, red, yellow, and blue) were
all but absent. Sometimes a little red became visible. A little more
often some quite obvious green would show up. But mostly this aurora
consisted of white glows of varying intensity -- often quite bright.
I've seen much better auroras as far as naked-eye color is concerned.

A weaker auroral glow engulfed the entire sky. Much brighter
homogeneous and rayed arcs were very common. The hour centered around
local midnight (7:00 UT) was quite active. Bits and pieces of a huge,
rayed arc extended from eastern to western horizons through a point
positioned perhaps 10 degrees south of my zenith. That point often
served as a center for bright, white rays to radiate outward in all
directions while long ribbons extended eastward and westward.

For the next phase of activity a long, broken, rapidly pulsating,
rayed arc positioned itself further south, crossing the southern
meridian at an altitude of about 40 degrees.

Besides the generally monochromatic white color, this aurora differed
from most others I've seen by it's very high-speed, high amplitude
light fluctuations -- particularly in the last hour or two of my
observing. It was somewhat reminiscent of a very intense,
cloud-to-cloud lightening show. This was most definitely *not* one of
those slow displays that show little change over tens of minutes.
This aurora showed rapid pulsations on split-second time scales.

I found myself dozing off as the 1:00 (8:00 UT) hour approached. My
last look at the sky was a few minutes after 1:00. Activity had
calmed down a good deal. The major auroral activity moved out of the
southern sky, limiting itself mostly to the northern sky. It was time
for some sleep.

So how did this aurora rate? If there had been quite a bit more color
I would have rated it as the best (or in a tie for the best) I've ever
seen. As it was, it was quite likely the most *active* (rapidly
changing structures over large expanses of sky for long periods of
time) I've ever seen; but I've seen others that covered just as much
sky, generated similar light levels (I think!), but had vivid reds,
yellows and greens. Regardless, this was certainly a major aurora
that deserves high points on the non-existant, auroral, richter scale.

Sketcher
To sketch is to see.