One of the things I'd like to do in my 4 years stay at 42° N was to see, at least, an aurora display. I frequently get aurora warnings from the Aurorawarn mailing list owned by spacew.com and another Astroalert list run by Sky and Telescope. Depending on solar activity, the number of warnings issued each year can vary. In my memory, it's typically less than 10 a year. Local weather conditions would cut the actual number of observable aurora events to a lot less than the number of issued warnings. Looking back, I could have observed a total of 3 aurora displays in 4 years, but I've seen only 1 out of those 3 because of circumstantial reasons --- I missed one of them because I had to stay overtime in the tutoring center, and consequently missed a ride from a friend to a dark site. As for the other I missed... I didn't get to the observing location at the right time.
I saw my first and only aurora display on Sep 7 2002 from the observatory on campus. I saw a faint arc, rather unlike light pollution, across the northern horizon between 8 and 9pm. It didn't take long for intense green rays started to appear in Big Dipper, Hercules and Draco. Activity shifted to Perseus and below Polaris at about half past 9. Red pulses could be seen in some parts of the sky. Aurora activity died down significantly after that, but the mysterious glow in the north lingered on for a few hours. Faint rays appeared after midnight, but these were nowhere as intense as those hours before. Here's an extract from the personal log entry I wrote the morning after the display.
The auroras! I can finally claim with confidence to have seen an aurora display! J was telling me about the AstroAlert notice he received and I had missed because I did not have internet connection in my apartment. I noticed a faint arc of light in the northern horizon just when he mentioned it. They were not much different from those I had seen in April/May a semester ago, which can well be passed off as clouds. Green rays started to appear in the southwest and extremely intense, at least for me, aurora activity ensued. These certainly could not have been clouds. Two visitors stopped by and witnessed the spectacle. One of them said she was T's roommate.
I was too excited for words when I saw the aurora activity intensify. I recalled noticing some semblance of curtain-like activity in the southwest when I decided to get J and M off the scope and onto the observing deck. Seconds later when I shifted my gaze back towards the sky, the rays became so much brighter! I also remember hearing police sirens in the distance, and I wondered if they were in any ways related to the aurora.
Rays from the aurora spanned these constellations: Ursa Major, Ursa Minor, Draco, Perseus, Cassiopeia, Bootes, Serpens, Hercules and even as high as the region near Lyra! I would rate this the second best astronomy event I had ever witnessed, after the great Leonids shower of 2001. Of course, this could not have been possible without the great viewing conditions that we enjoyed tonight. The moon was in new phase, the skies were totally clear, and seeing was good.
A fruitful observing session followed. I bagged targets which I've always wanted to catch. M76 "Little Dumbbell" was one of them. The others: Saturn Nebula, M92 GC, M7x GX, and one more which I can't recall. We caught glimpses of some the early risers of the winter constellation without having to brave the frosty upstate winter. Well, it wasn't so cold tonight.
back to sleep
0450, Sep 08 2002
I continued to keep watch on aurora warnings over the years. There had been some good displays that were obscured by cloud cover, which was at times extensive enough to cover the entire N Am. I remember nights when I stepped out of my apartment to monitor the cloud cover every half hour and refreshed the spacew.com aurora sightings page every 10 minutes just to be sure I wasn't missing anything. Incidentally, shortwave radio listeners like myself get to monitor aurora activity indoors from our radio sets. For reasons I shall not elaborate here, shortwave propagation is disrupted when an aurora is in progress. When all I hear is static from the usually strong BBC Carribean transmission frequency at 5975 kHz, something is up in the ionosphere.
It'll be a while before I see my second one, now that I'm back in the vicinity of 0° latitude for an unknown number of years.
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