Solar Terrestrial Activity Report [Image] Last update July 13, 2000 at 03:25 UTC. /No updates will be posted July 14-15. From July 16 until July 30 this page will likely be updated occasionally as I will be on vacation. Daily updates will resume on August 4/ [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update July 1, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update July 1, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update July 1, 2000)] [Historical solar and geomagnetic data charts 1954-2000 (last update April 12, 2000)] Recent development The geomagnetic field was quiet to active on July 12. Solar wind speed ranged between 464 and 582 km/sec. Solar flare activity was high. Solar flux was 255.1 (value taken from measurement at 17h UTC, solar flux at 20h UTC was highly influenced by flare activity), the planetary A index was 12 (3-hour K indices: 4323 2323, Boulder K indices: 4313 1233). Region 9066 rotated over the west limb early today. Region 9068 was quiet and stable and is rotating off the visible disk. Region 9069 developed slowly and could produce minor M class flares before rotating off the visible disk late on July 14. Region 9070 developed further and has a magnetic delta configuration within the main penumbra. The region could produce another major flare before rotating off the visible disk on July 15. Region 9073 decayed slowly and could produce a minor M class flare. Region 9076 was quiet and stable. Region 9077 lost the magnetic delta configuration within the main penumbra following the X flare. Another magnetic delta is still present in a trailing penumbra. Further major flare activity is possible, including an X flare. Region 9078 decayed into spotless plage Regions 9079 and 9080 were quiet and stable. Region 9081 developed slowly and could be capable of producing a minor M flare. Region 9082 developed slowly and was quiet. Region 9083 decayed into spotless plage. New region 9084 emerged in the northeast quadrant. New region 9085 rotated into view at the northeast limb. An interesting active region is at the southeast limb, it could produce further M class flares. Flares and CMEs A total of 2 C, 5 M and 1 X class events were observed on July 12. A long duration M1.3 event peaked at 03:25 UTC, its source was a region at the southeast limb. Region 9077 produced an M1.2/1N flare at 05:02, a C5.3 flare at 09:15 and a major X1.9/2B flare at 10:37 (accompanied by a moderately strong type IV sweep and possibly a weak CME). Region 9070 generated a long duration M1 event peaking at 16:52, a major M5.7/2F flare at 18:49 and a long duration M1.6 event peaking at 20:10 UTC. The latter event was accompanied by a moderately strong type II sweep and a likely CME (no LASCO images are yet available from the evening of July 12). An optically uncorrelated M1.9 flare was observed at 21:40 UTC, its origin may have been the region at the southeast limb. July 11: Region 9077 generated a long duration X1.0/2N event peaking at 13:10 UTC. A very large full halo coronal mass ejection was observed in connection with the X1 event. The CME will impact Earth, most likely sometime between noon on July 13 and noon on July 14. This could result in active to severe storming. July 10: Region 9077 produced a long duration major M5.7/2B event peaking at 21:42 UTC. Strong type II and IV sweeps were recorded during the major flare. A full halo coronal mass ejection was observed in LASCO C3 starting at 22:18 UTC. Most of the mass headed off towards the northeast, however, there is a possibility for minor or major storming at Earth on July 13 or 14. The background x-ray flux is at the class C3 level. Coronal holes A small coronal hole just to the west of region 9077 will rotate into a geoeffective position on July 12-13 and could cause unsettled to active intervals on July 15-16. Forecast The geomagnetic field is expected to be quiet to major or severe storm on July 13-14. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is very poor. Coronal holes (1) Coronal mass M and X class flares (3) ejections (2) [Coronal hole indicator][CME indicator] [M and X class flare indicator] 1) Effects from a coronal hole could reach earth within the next 5 days. 2) Material from a CME is likely to impact earth within 96 hours. 3) There is a possibility of either M or X class flares within the next 48 hours. Green: 0-20% probability, Yellow: 20-60% probability, Red: 60-100% probability. Active solar regions (Recent map) Solar Date Actual Location region numbered no. at Area Classification Comment sunspots midnight 9066 20000629 2 N13W88 0020 CRO 9068 20000701 4 S17W80 0190 DAO 9069 20000701 19 S17W64 0470 EAI beta-gamma 9070 20000702 14 N19W63 0680 FKO beta-gamma-delta 9072 20000705 N16W76 plage 9073 20000705 11 S19W49 0270 EAI 9074 20000705 N13W24 plage 9075 20000706 N06W09 plage 9076 20000706 2 S21W08 0020 CSO 9077 20000707 38 N17E16 0940 FKC beta-gamma-delta 9078 20000707 S14E01 plage 9079 20000709 1 S28E25 0060 HAX 9080 20000709 1 N26E40 0030 HSX 9081 20000711 6 N02E55 0170 DAO 9082 20000711 8 S12E21 0030 CSO 9083 20000711 S18W34 plage 9084 20000712 3 N20E35 0020 CRO 9085 20000712 2 N13E69 0050 DRO Total number of sunspots: 111 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.06 169.8 137.7 93.1 (+2.6) 1999.07 165.6 113.5 94.3 (+1.2) 1999.08 170.7 93.7 97.5 (+3.2) 1999.09 135.7 71.5 102.3 (+4.8) 1999.10 164.8 116.7 107.8 (+5.5) 1999.11 191.5 133.2 110.9 (+3.1) 1999.12 169.8 84.6 111.0 (+0.1) 2000.01 158.1 90.1 (110.9 predicted, -0.1) 2000.02 174.1 112.9 (113.7 predicted, +2.8) 2000.03 208.2 138.5 (117.9 predicted, +4.2) 2000.04 184.2 125.3 (120.0 predicted, +2.1) 2000.05 184.9 120.8 (120.8 predicted, +0.8) 2000.06 179.8 124.9 2000.07 194.5 (1) 84.0 (2) 1) Running average based on the daily 20:00 UTC solar flux value at 2800 MHz. 2) Unofficial, accumulated value. The official value is typically 25-40% less. This report has been prepared by Jan Alvestad. It is based partly on my own observations and interpretations, and partly on data from sources in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]