Solar Terrestrial Activity Report [Image] Last update June 11, 2001 at 02:25 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update June 3, 2001)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update June 4, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update June 4, 2001)] [Historical solar and geomagnetic data charts 1954-2001 (last update April 8, 2001)] Recent development The geomagnetic field was unsettled to minor storm on June 10. Solar wind speed ranged between 515 and 656 km/sec under the influence of a weakening coronal stream. Solar flare activity was low. Solar flux was 163.0, the planetary A index was 20 (3-hour K indices: 5344 3433, Boulder K indices: 5333 3322). Region 9484 was quiet rotated off the visible disk. Region 9487 became more complex with the emergence of a weak magnetic delta at the tail end of the penumbra containing most of the region's spots. Further C flares are likely and there is a chance of a minor M class flare as well. Region 9488 decayed slowly and quietly. Region 9489 appeared to be slowly decaying by the end of the day. Minor M class flares are possible. Region 9491 was quiet and stable. Region 9492 decayed further and was quiet. Region 9493 decayed slowly and quietly. Region 9494 developed slowly and again has a magnetic delta. Minor M class flares are likely and there is a chance of a major flare as well. Region 9495 was quiet and stable. Region 9496 decayed and was quiet. New region 9497 in the southeast quadrant was finally numbered, the region developed its first spot on June 8. New region 9498 rotated into view at the northeast limb. Another region is currently rotating into view at the southeast limb. Flares and CMEs A total of 16 C class events were recorded on June 9. Region 9494 produced a C9.7 flare at 01:04, a C6.3 flare at 09:02, a C2.2 flare at 11:26, a C2.4 flare at 12:47, a C2.5 flare at 15:48 and a C1.0 flare at 17:39 UTC. Region 9487 generated a C2.7 flare at 11:56, a C2.4 flare at 19:49 and a C2.0 flare at 21:23 UTC. Region 9497 was the source of a C1.9 flare at 12:14 UTC, while region 9489 managed a C1.1 flare at 17:39 UTC. June 8: Region 9488 produced a C6.0/1N flare at 02:28 UTC. A moderate type II radio sweep was recorded. The event occurred near the central meridian and may have caused a geoeffective CME. If it did it is likely to impact Earth sometime between noon on June 10 and the early hours of June 11 and cause unsettled to active conditions. The background x-ray flux is at the class B8 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to active on June 11. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is poor to 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 no. Location region numbered sunspots at Area Classification Comment midnight 9484 2001.06.01 1 S06W92 0070 HSX 9485 2001.06.01 S23W45 plage 9487 2001.06.02 9 N21W30 0160 CAO beta-delta? 9488 2001.06.03 10 S18W32 0070 CAO 9489 2001.06.05 31 N18W17 0220 EAI beta-gamma 9490 2001.06.05 S16W17 plage 9491 2001.06.05 1 N25E10 0130 HAX 9492 2001.06.06 9 N20E11 0130 DAO 9493 2001.06.06 6 N06E25 0130 FAO beta-gamma 9494 2001.06.08 11 S08W57 0410 EKI beta-delta 9495 2001.06.08 7 N04W03 0030 CSO 9496 2001.06.09 1 N09W47 0010 HRX 9497 2001.06.10 10 S10E27 0040 DSO 9498 2001.06.10 1 N22E58 0030 HSX Total number of sunspots: 97 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 2000.03 208.2 138.5 119.9 (+3.1) 2000.04 184.2 125.5 120.8 (+0.9) cycle 23 sunspot max. 2000.05 184.9 121.6 119.0 (-1.8) 2000.06 179.8 124.9 118.7 (-0.3) 2000.07 202.3 170.1 119.7 (+1.0) 2000.08 163.0 130.5 118.6 (-1.1) 2000.09 182.1 109.7 116.2 (-2.4) 2000.10 167.4 99.4 114.5 (-1.7) 2000.11 178.8 106.8 112.8 (-1.7) 2000.12 173.6 104.4 (110.5 predicted, -2.3) 2001.01 166.6 95.6 (106.8 predicted, -3.7) 2001.02 146.6 80.6 (102.4 predicted, -4.4) 2001.03 177.7 113.5 (98.8 predicted, -3.6) 2001.04 177.7 108.2 (97.6 predicted, -1.2) 2001.05 147.1 97.3 (96.9 predicted, -0.7) 2001.06 156.2 (1) 55.6 (2) (94.2 predicted, -2.7) 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 25-40% 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 noted in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ Do you know about the survey which will be held this Summer among the listeners of WWV and WWVH? There is information about this survey at 16 minutes past the hour on WWV and at 47 minutes past the hour on WWVH. If you want to participate send an email with your name and address. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]