Solar Terrestrial Activity Report [Image] Last update July 11, 2002 at 03:30 UTC. Minor update posted at 19:21 UTC. [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, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update July 1, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update July 1, 2002)] [Historical solar and geomagnetic data charts 1954-2002 (last update April 13, 2002)] Recent development The geomagnetic field was quiet to unsettled on July 10. Solar wind speed ranged between 413 and 518 km/sec, decreasing towards the end of the day.. Solar flare activity was low. Solar flux was 128.8 (the lowest measured solar flux at 20h UTC since August 2, 2001), the planetary A index was 11 (3-hour planetary K indices: 3333 2233, Boulder K indices: 3322 1222). Region 10019 decayed further and is quickly losing its southern penumbra. Region 10021 decayed and was spotless by noon. The region is rotating over the southwest limb. Region 10022 decayed and was spotless early in the day. Region 10023 developed slowly early in the day, then decayed and appears to be spotless early on July 11. Region 10024 continued to decay quickly and had only a couple of small spots left by midnight, the region is likely to become spotless today. Region 10025 displayed some activity right after noon, but was otherwise quiet and stable. Region 10028 was quiet and stable. Region 10029 developed slowly and quietly. Region 10030 developed slowly with most of the development occurring in the northern part of the region. There is a strong magnetic delta structure within the main penumbra and another delta has developed in a smaller penumbra in the northeastern section. Further development is likely and the region could be capable of producing a major flare. Late on July 10 a small spotted region rotated into view at the northeast limb. Comment added at 19:21 UTC on July 11: Region 10030 has developed dramatically today with the very rapid emergence of new and strong magnetic areas in the eastern and northeastern part of the region. The region produced its first major flare at 14:51 UTC, an M5.8 event. Further M class flaring is very likely and the chance of an X class flare is increasing. Flares and CMEs A total of 4 C class events was recorded on July 10. Region 10030 produced a C1.1 flare at 01:50 UTC. Region 10025 generated a C1.0 flare at 12:50 and a C2.7 flare at 13:33 UTC. The background x-ray flux is at the class B3-B4 level. Coronal holes A coronal hole in the southern hemisphere in the southern hemisphere could rotate into a geoeffective position on July 14. Forecast The geomagnetic field is expected to be quiet to unsettled on July 11-13. 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 Location region numbered no. at Area Classification Comment sunspots midnight 10019 2002.06.29 6 S19W70 0240 DSO area too large, estimated at 0150 10020 2002.07.02 N00W43 plage 10021 2002.07.03 1 S28W87 0030 HAX spotless by noon 10022 2002.07.03 1 S18W59 0000 AXX now spotless 10023 2002.07.03 2 S22W38 0010 HRX now spotless 10024 2002.07.03 4 S35W26 0020 CSO 10025 2002.07.04 1 S20W03 0030 HSX 10027 2002.07.07 S15W13 plage 10028 2002.07.08 2 S16E12 0010 BXO 10029 2002.07.08 6 S14E25 0040 DSO beta-gamma-delta 10030 2002.07.09 5 N19E62 0460 EKO too few spots, at least 14 observed during early evening Total number of sunspots: 28 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 2000.04 184.2 125.5 120.8 cycle 23 sunspot max. 2000.07 202.3 170.1 119.8 2001.06 173.0 134.0 109.8 (+1.2) 2001.07 131.3 81.8 111.7 (+1.9) 2001.08 162.9 106.4 113.6 (+1.8) 2001.09 233.2 150.7 114.1 (+0.5) 2001.10 207.6 125.5 114.0 (-0.1) 2001.11 210.6 106.5 115.5 (+1.5) 2001.12 235.1 132.2 114.6 (-0.9) 2002.01 226.6 114.1 (112.7 predicted, -1.9) 2002.02 205.0 107.4 (111.3 predicted, -1.4) 2002.03 179.5 98.4 (106.6 predicted, -4.7) 2002.04 189.8 120.4 (100.7 predicted, -5.9) 2002.05 178.4 120.8 (96.3 predicted, -4.4) 2002.06 148.7 88.5 (91.7 predicted, -4.6) 2002.07 139.2 (1) 40.5 (2) (86.9 predicted, -4.8) 1) Running average based on the daily 20:00 UT solar flux value at 2800 MHz. 2) Unofficial, accumulated value based on the Boulder (SEC/NOAA) sunspot number. The official international sunspot number is typically 25-45% 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 noted in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News]