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SUNSPOT 798 (August + September 2005)

M5 Flare on August 22nd K Index on August 24th Image of farside of sun on Sept 1st Farside CME, Sept. 5th X17 Flare, Sept. 7th GOES X-Ray Flux, Sept. 7th X6 Flare, Sept. 9th K Index Sept. 11th - 13th X Flare, Sept. 13th SUNSPOT 798: This was no ordinary sunspot. During the months of August and September 2005, Sunspot 798 grew into one of the bigger spots on record and rounded the sun twice and exploded countless M Flares and atleast 9 X flares including one of the biggest on record, a monster X 17 flare on Sept 7th at 1740 UT. The History of 798 The spot was non existant on August 18th, and formed midway across the earth facing side of the sun the next day on August 19th. By August 20th the spot was 5 times earth's diameter. On August 22nd 798 exploded an M5 class flare, followed by an M2 on August 23rd which was a sign of things to come. The explosions hurled a pair on coronal mass ejections towards earth and set off a strong geomagnetic storm in the early morning hours of August 24th. The K Index at the peak was 9+. Luckily i was able to make many aurora contacts on 6M that morning with some great signals. See below for grid's worked during this opening. Aurora was seen as far south as Utah and Colorado. By August 25th the spot rounded the western limb of the sun and the threat of earth directed flares dropped except for a tiny M1 flare from sunspot 803 on August 28th. However, the best was yet to come. -It must be noted that on August 31st, a south tilting magnetic field, combined with a strong solar wind sparked another aurora opening on 6 meter's with many nice contacts. See below for grid's worked during this opening. Using the technique "helioseismic holography", which is basically a holographic image of the farside "backside" of the sun, we knew the sunspot was still alive and still very big. There was also some explosions on the farside as well. Could the spot maintain this energy ? You bet ya! On Sept. 7th, one of the biggest flares in history exploded from 798. An X17 monster flare erupted, however the spot was still not around the sun's eastern limb yet so the blast was not earth directed. But it was a promising sign and sure enough more X flares followed. An X5 on Sept. 8th, X6 on Sept. 9th, X2 on Sept. 10th was just a great show of how powerful this sunspot was. Because the spot was now coming into earth's view, Aurora's that followed were amazing. During the weekend of Sept 10-12th was the ARRL September VHF QSO Party. The contest was pretty slow here with a lack of activity. However late Sept 10th and early Sept 11th when a CME swept past earth, what followed was one of the best aurora openings i have ever experienced. Because the contest was in full swing, there was loads of band activity and amazing signals. I was able to work some west coast as well, which was a treat. I had to step outside for about 10 minutes, luckily it was a clear night and the visual display of northern lights was incredible. Excited, i came right back in and was working full force in the contest working 6 meter's well into the early hours. See below for grid's worked and Audio Files during the contest. Aurora Sept. 11 in Green, NY. The solar wind was quite strong at over 800 km/s during the period of Sept 11 - 13th which continued to produce some auroral conditions on 6 meter's. On Sept 13th, an X1 Flare exploded from 798 and in the days after that a few more M Flare's happened, but none of them produced much activity on earth.. and the solar wind was finally starting to slow down. 798 finally made its way around the sun's western limb and on Sept. 18th disappeared. That marked the end of a great period of solar activity, which happened mind you during the solar cycle's so called minimum. 798 crossing Sept. 7-18 GRID'S WORKED: Map of Grids Worked (click to enlarge) August 24th EN 42,43,44,84,91 FN 10,21,30,31,34,37,42,46,54,57,74 FM 18,28,29 August 31st EN 84 FN 00,02,30,31,34,36,41,42,74 FM 18 September 11th CO 88 DN 06 DO 61 EN 35,36,37,41,44,54,61,71,81,82,91,93 FN 00,03,04,10,20,21,22,23,31,34,35,41,43,44,45,46,48,57,74 FM 08,09,16,18,19,29 September 12th FN 31,48 FM 19 AUDIO FILES: Click HERE for the 6M Sound File section.