Solar Terrestrial Activity Report [Image] Last update May 15, 2000 at 01:30 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update May 2, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update May 2, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update May 2, 2000)] [Historical solar and geomagnetic data charts 1954-2000 (last update April 12, 2000)] Recent development The geomagnetic field was quiet to active on May 14. Solar wind speed ranged between 407 and 568 km/sec. Solar flare activity was moderate. Solar flux was 232.5, the planetary A index was 12 (3-hour K indices: 4422 3232, Boulder K indices: 5422 3222). Regions 8983 and 8987 decayed into spotless plage. Region 8989 decayed slowly but could still produce C flares and an isolated minor M flare. Region 8990 decayed slowly and was quiet. Occasional C flares or a minor M flare are possible. Region 8991 decayed slowly and was quiet. Region 8992 was quiet and stable. Region 8993 was mostly unchanged and will likely continue to produce C flares, occasional M flares are possible. Region 8994 reemerged with a couple of spots. Region 8996 did not change significantly and remains a large region capable of producing major flares, even X class flares. Region 8997 was quiet and stable. Region 8998 developed slowly and could produce M flares. Region 8999 was quiet and stable, as was region 9000. Region 9001 decayed into spotless plage. New region 9002 rotated partly into view at the northeast limb, the region is quite active and could produce M flares. New region 8993 emerged in the southwest quadrant. Flares and CMEs A total of 10 C flares and 1 M flare were observed on May 14. Region 8993 produced a C5.2 flare at 04:01, an M1.0 flare at 08:05, a C5.1 flare at 19:47 UTC and a C3.6 flare at 22:47 UTC. Region 8996 was the source of a C7.5 flare at 09:18 and a C7.3 flare at 10:38 UTC. Region 8998 was the source of a C6.6 flare at 16:48 and a C3.6 flare at 22:!9 UTC. Region 8989 managed a C4.8 flare 14:32 UTC. An apparently full halo CME was observed early on May 14 following several filament eruptions, 1 from the northeast hemisphere, 1 across the equator in the western hemisphere and another over the southwest quadrant. All occurred late on May 13 and early on May 14. The CME could cause a disturbance on May 17. The background x-ray flux is at the class C2 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to active on May 15 and quiet to unsettled on May 16. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is 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 no. Location at region numbered sunspots midnight Area Classification Comment 8983 20000504 N26W80 plage 8985 20000505 N12W66 plage 8987 20000507 N09W88 plage 8989 20000507 16 N16W54 0320 DKI beta-gamma 8990 20000507 28 N14W35 0230 DAI beta-gamma 8991 20000508 5 N16W09 0020 CSO 8992 20000509 4 N11E09 0020 CAO 8993 20000508 15 S23W58 0290 EKI 8994 20000510 N08W56 plage 8995 20000511 S19W39 plage 8996 20000511 26 S21E44 1140 EKC beta-gamma 8997 20000511 3 S16E22 0010 BXO 8998 20000512 19 S13E54 0410 FAI beta-gamma 8999 20000513 5 N20E55 0060 CSO 9000 20000513 4 N08E00 0010 BXO 9001 20000513 N16W18 plage 9002 20000514 1 N18E76 0190 HHX 9003 20000514 5 S18E26 0010 BXO Total number of sunspots: 131 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.04 117.2 63.9 85.5 (+1.7) 1999.05 148.4 106.3 90.5 (+5.0) 1999.06 169.8 137.7 93.1 (+2.6) 1999.07 165.6 113.5 94.5 (+1.4) 1999.08 170.7 93.7 97.4 (+2.9) 1999.09 135.7 71.5 102.3 (+4.8) 1999.10 164.8 116.7 107.7 (+5.4) 1999.11 191.5 133.2 (109.8 predicted, +2.1) 1999.12 169.8 84.6 (108.2 predicted, -1.6) 2000.01 158.1 90.2 (108.6 predicted, +0.4) 2000.02 174.1 112.3 (112.0 predicted, +3.4) 2000.03 208.2 138.2 (115.8 predicted, +3.8) 2000.04 184.2 125.3 2000.05 161.7 (1) 71.3 (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]