Aurora 13th March 1989 A personal viewpoint It was 25 year ago that I caught my first ever “all sky” aurora from Dewarton, near Dalkeith in Midlothian (55 52N, 002 58W). The memories have faded somewhat over the years, but like all big lifetime events, I can recall certain things, almost as if it was yesterday. I used to monitor the sun on a regular basis back then, projecting an image of the sun from binoculars onto a sheet of paper, so I was aware that there was a massive sunspot rotating towards the centre of the sun, and on the 8th of March I viewed red colours in an aurora for the very first time from my home near Campbeltown in Argyll (55 25N, 005 37W). I travelled up to Edinburgh over the weekend, and remember watching the Sky at Night late on Sunday the 12th, when Patrick Moore mentioned the possibility of a big aurora on Monday night, following a solar flare and coronal mass ejection (cme) on the 10th. I first caught sight of the display whilst driving into Dalkeith around 8 O clock. The road near Edgehead is high above Dalkeith with an unobstructed view north over Edinburgh and the Firth Of Forth, and I have vivid memories of an extremely bright rayed band, around 20 or 30 degrees above the northern horizon, dancing above Arthur Seat and the bright lights of Edinburgh. I was back at my parents house in Dewarton by around 8 30, where I viewed the aurora from a farm track with good views from north through the east to the south. The climax of the display occurred between around 9 30 and 10, with bright rays overhead and to the south, whilst the northern sky was pretty much dark below around 40 degrees. I was able to catch some images using my Olympus OM 20, with 400 ASA Kodachrome slide film, but unfortunately for some reason I didn’t have a tripod, and the 50mm lens was a bit on the narrow side for such a big display. I think it must have been cloudy for a time around midnight, but I do remember looking north at around 4 am and seeing massive purple/blue rays, extending up to around 80 degrees above the northern horizon. The following information was obtained from wikipedia, and the book “Storms from the Sun” Sunspot 5395 Sunspot 5395 was very large, measuring 43,000 miles across, and roughly 54 times the size of Earth. The sunspot produced a total of 195 flares during its earth facing transit from the 6th to 19th March, including 48 M class and 11 X class flares, and 36 cme’s were observed by NASA’s Solar Maximum Mission (SMM). The largest flare was an X15 on March 6th, which may account for the red aurora I observed on the 8th. Another X class flare was observed on the 10th, as the sunspot crossed the middle of the solar disk, with the associated cme producing the massive geomagnetic storm on the 13th. Tropical aurora The aurora on the 13th could be seen as far south as Texas and Florida, and as this occurred during the Cold War, an unknown number of people worried that a nuclear first-strike might be in progress. It was seen widely in Europe, reaching as far south ad Portugal, Spain and Hungry. In the southern Hemisphere auroras were observed in New Zealand, Australia, and further north over South Africa. There were even reports of aurora from the tropics, where mystified observers watched the display from Cancun, Mexico, Grand Cayman Island, Honduras, and Dominica. Wake up call Until this event, spaceweather was not taken all that seriously, but the effects of this storm made us realise just how much spaceweather could disrupt our modern way of life. - Induced ground currents led to a massive power cut in Quebec, affecting much of the state and lasting for more than 9 hours. Power cuts were not just confined to Canada, with a considerable amount of damage to transformers and other electrical equipment across North America and northern Europe. - Navigation was disrupted all around the world, with compasses deviating by as much as 10 degrees, and several North Sea oil companies stopped drilling as the compasses that guided the drilling were way of course. In a few instances GPS systems were severely degraded or gave outright erroneous positioning information. - At the height of the storm satellites felt the full force of the sun, as the density of the upper atmosphere increased by five to nine times normal levels, mainly due to the compression of the magnetosphere. This resulted in increased friction and drag on low earth orbiting satellites, causing them to literally fall out of there normal orbits. Ironically, this led to the demise of the Solar Maximum Mission, which dropped a ½ mile in one day, and a total of 3 miles during the event, before eventually burning up in the earth’s atmosphere on the 2nd December 1989.
Posted on: Thu, 13 Mar 2014 11:25:07 +0000
Trending Topics
Recently Viewed Topics
© 2015