Wiki
-
Length
4:12
(preceding the Auroral Chorus several hours later)
About half an hour before sunset, we reached Alberta, and stopped briefly to snap a photograph of
us standing next to the "Entering Alberta, Wild Rose Country" sign. Whew!, we had crossed into yet
another huge and awesome province. Remembering that the next morning was "VLF Sunday"a
date arranged in advance by Michael Mideke to record natural VLF radio at pre-arranged times, we
started looking for a back road off of what was now Alberta Provincial Highway 12. We were in a sparsely populated and rather hilly area near Kirriemuir and Monitor, AB, and hoped we could find a location to spend the night which was away from electric power-lines by at least a mile. As we drove down the highway, we tossed our heads left and right, spying a few interesting looking dirt and gravel roads on both sides of the main highway.
Braking to a halt on the empty highway, we did yet another of our multiple point turns in the van and headed back the other way. The first gravel road we chose ended up looking a bit too well-traveled and also not far enough from AC power-lines. The second choice couldn't have been better– a lightly rutted dirt (and mud) track into some low hills and trees next to an arroyo. The road terminated at what appeared to be ranch homestead with only a trailer and fallen-down windmill atop one of the small hills.
A quick check with my WR-3 confirmed this level hill-top location was great for natural radio listening, being quite some distance from electric wires. With some trepidation since we didn't like the idea of trespassing, we walked up to the trailer prepared to ask permission to park nearby. But, nobody was home and the place looked like it had been unoccupied for at least a week, so we elected to stay and set up the WR-4B VLF receiver's antenna mast then ate dinner
while watching the perfectly clear sky turn colors as night approached. It felt like it was going to be
a cold night, though the very dry air would make the cold bite less, and I hoped the aurora would
return.
At about 3 a.m. MDT, I awoke and was startled then joyous to see the northern sky filled with a
green glow. Looking closer, I also spied faint bursts of green "splotches" moving ("squirting") in a
left-to-right (west-to-east) direction! Wow, it was much better than the night before! Apparently, a
minor magnetic storm was happening, though I really wasn't alerted to it since the geo-magnetic
"indices" put out on shortwave time and frequency standard station WWV from Colorado was
reporting only "unsettled" magnetic conditions. I quickly awoke Gail, who had missed out on seeing the fainter aurora the night before. The next thing I did was turn on the WR-4B whistler receiver and start up the tape recorder. I was instantly rewarded by a faint squawking sound of "chorus"
as well as weird tones slowly rising then falling. When these weird "sliding tones" would appear, the
aurora would slightly brighten and the "squirting green splotches" also seemed to speed up!
By this time, it was at or below freezing, and frost was rapidly building up on the outside of the van's
windows though the air inside the van had been considerably warmer–at least until I threw open
the back doors and began watching the auroral show while still tucked tightly in my sleeping bag.
Gail borrowed the whistler receiver's headphones and listened to the weird VLF radio sounds coming forth, but leepiness overcame her again and she dozed off. As the initial excitement wore off, I also felt very sleepy again and decided to doze for a while with the tape recorded still running–I at least wouldn't miss out on the great VLF radio sounds.
As the 1100 UTC period approached, I flipped the cassette over and prepared to tape the auroral
radio chorus, which by this time was become quite vigorous. Alas, I waited until about 1104 UTC to begin the taping, thinking the appointed monitoring time was to begin at 1105 UTC, when actually it began at 1100. I rolled the tape and taped an entire side of a C-90 (45 minutes) of the fantastic Alberta auroral chorus. This recording was made several hours before the actual aurora was visible, at around 10:45 p.m. local Mountain Daylight Time."
Techie Notes: (Slow descending, breathy/windy sounding whistler trains recorded in eastern
Alberta (near Monitor and Kirremuir off of Hwy. 12) at approx. 0445 UT on 26 Sept. 1993.Two hours
later, there was visible aurora and the VLF auroral chorus began at approx. 1015 UT Weak background power-line hum (uninterrupted recording of 2:25) to end of side A, repeated at start of side
B)
Track descriptions on Last.fm are editable by everyone. Feel free to contribute!
All user-contributed text on this page is available under the Creative Commons Attribution-ShareAlike License; additional terms may apply.