Solar Terrestrial Activity Report [Image] Last update October 14, 2001 at 02:15 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update October 3, 2001)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update October 3, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update October 3, 2001)] [Historical solar and geomagnetic data charts 1954-2001 (last update July 27, 2001)] Recent development The geomagnetic field was quiet to unsettled on October 13. Solar wind speed ranged between 399 and 471 km/sec. Solar flare activity was low. Solar flux was 179.5, the planetary A index was 10 (3-hour K indices: 3333 2221, Boulder K indices: 3333 3222). Region 9650 was spotless all day in all available images. Region 9653 was quiet and stable. Region 9655 decayed slowly and quietly. Region 9657 decayed quietly. Region 9658 did not change significantly and may be capable of minor M class flare production. Region 9660 decayed slowly and quietly. Region 9661 developed slowly and could produce M class flares, major M or X class flares are possible. Region 9662 developed slowly and could produce C class flares. Region 9663 was quiet and stable. New region 9665 emerged in the southwest quadrant but is already spotless. Flares and CMEs A total of 6 C class events were recorded on October 13. Region 9658 produced a C5.3 flare at 05:23, a weak type II radio sweep was associated with this event. Spotless region 9648 was the source of a C1.2 flare at 09:06 UTC, while region 9661 managed a C2.6 flare at 12:32 UTC. The background x-ray flux is at the class B6 level. Coronal holes A poorly defined coronal hole in the southern hemisphere was in a geoeffective position on October 12-13. Forecast The geomagnetic field is expected to be quiet to unsettled on October 14 and quiet to active on October 15. 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 Location region numbered no. at Area Classification Comment sunspots midnight 9648 2001.10.02 S06W73 plage 9650 2001.10.03 2 S17W56 0010 BXO actually spotless 9653 2001.10.04 7 S22W40 0060 DAO 9655 2001.10.06 4 S22W26 0030 CSO 9657 2001.10.08 1 N22E04 0010 HSX 9658 2001.10.09 16 S15E18 0190 FSI 9659 2001.10.10 N03W22 plage 9660 2001.10.10 5 N13W21 0020 CSO 9661 2001.10.10 16 N15E42 0720 DKI beta-delta 9662 2001.10.11 11 N09E15 0070 DAO 9663 2001.10.11 1 S15E37 0020 HSX 9664 2001.10.12 N07E03 plage 9665 2001.10.13 3 S26W57 0010 BXO now spotless Total number of sunspots: 66 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. 2000.07 202.3 170.1 119.7 2000.09 182.1 109.7 116.3 (-2.3) 2000.10 167.4 99.4 114.5 (-1.8) 2000.11 178.8 106.8 112.8 (-1.7) 2000.12 173.6 104.4 112.1 (-0.7) 2001.01 166.6 95.6 108.8 (-3.3) 2001.02 146.6 80.6 104.1 (-4.7) 2001.03 177.7 113.5 104.8 (+0.7) 2001.04 177.7 108.2 (107.7 predicted, +2.9) 2001.05 147.1 97.3 (108.1 predicted, +0.4) 2001.06 173.0 134.0 (106.3 predicted, -1.8) 2001.07 131.3 82.2 (105.1 predicted, -1.2) 2001.08 162.9 106.8 (105.7 predicted, +0.6) 2001.09 233.2 150.7 (105.1 predicted, -0.6) 2001.10 183.5 (1) 75.1 (2) (102.3 predicted, -2.8) 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 25-40% 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. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]