Solar Terrestrial Activity Report [Image] Last update October 9, 2002 at 03:30 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update October 2, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update October, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update October 2, 2002)] [Historical solar and geomagnetic data charts 1954-2002 (last update August 16, 2002)] Recent activity The geomagnetic field was unsettled to major storm on October 8. Solar wind speed ranged between 413 and 530 km/sec, slowly decreasing after 08h UTC. Solar flare activity was low. Solar flux was 165.4, the planetary A index was 34 (S.T.A.R. calculated average value based on three hour Ap indices: 35.1). Three hour interval K indices: 46454433 (planetary), 46344432 (Boulder). The background x-ray flux is at the class B6 level. At midnight there were 13 spotted regions on the visible disk, only 8 of which were numbered. Region 10137 decayed further and lost all trailing spots, the region will rotate out of view at the southwest limb today. Region 10139 decayed with most of the leader spots disappearing. The large penumbra containing a magnetic delta structure actually expanded slightly. The negative polarity spots in the southeast seem to be moving westwards faster than the positive spots in the north. If this development continues the magnetic delta will strengthen today and tomorrow with an increasing chance of M class flares. Flares: C1.1 at 07:46, C1.2 at 15:11 and C1.6 at 23:27 UTC. Region 10140 was mostly quiet and stable. Flare: C1.6 at 07:21 UTC. Region 10141 decayed quickly. At the current rate of decay this region will soon become spotless. Region 10142 was quiet and stable. Region 10143 developed slowly. The inversion line is generally running east west and polarities are currently intermixed. Further development is likely. Region 10144 developed slowly and quietly. The positive and negative polarity areas have separated and the region is unlikely to develop further unless new flux emerges. New region 10145 rotated into view at the northeast limb. Spotted regions which currently have not been numbered: 1. Several small spots were observed 4-9 degrees longitude west of region 10140. This area has decayed slightly over the last day. 2. A new region emerged east of region 10140 and was located at S10E37 at midnight. Further development is likely. 3. Late in the day a new region emerged in the southeast quadrant near the central meridian. This small region was located at S10E07 at midnight. 4. Late in the day a new region rotated into partially into view at the northeast limb. This region was located near N15E80 at midnight. 5. A small region near the southeast limb rotated into view late on October 7 and has been unchanged since then. Coronal mass ejections (CMEs) October 6-8: No obviously geoeffective CMEs were observed during the period. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to active on October 9 and quiet unsettled on October 10-12. 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) SEC Solar Date number Location region numbered of at Area Classification Comment spots midnight 10137 2002.09.29 1 S20W75 0130 HSX beta-gamma-delta 10139 2002.10.02 28 N11W07 0560 EKI classification DKC at midnight 10140 2002.10.04 1 S08E25 0160 HSX location S08E28 at midnight classification DAO at 10141 2002.10.05 4 S08W23 0040 AXX midnight with an area of 0020 10142 2002.10.05 1 N05E22 0020 HSX beta-gamma 10143 2002.10.07 5 S17W51 0030 DAO 13 spots observed late in the day, area near 0100 area at least 0090 at 10144 2002.10.07 7 N12E30 0060 DSO midnight, classification DAO 10145 2002.10.08 1 N12E76 0010 HSX area nearly 0100 at midnight. Typo? ? emerged (6) S08E22 0010 BXO 2002.10.05 ? visible on (1) S15E60 0010 AXX 2002.10.07 ? emerged (6) S10E37 0030 DAO 2002.10.08 ? emerged (2) S10E07 0010 HSX 2002.10.08 ? visible on (1) N15E80 0150 HSX 2002.10.08 Total number of sunspots: 48 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 2001.09 233.2 150.7 114.1 (+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) 2002.01 226.6 114.1 113.5 (-1.1) 2002.02 205.0 107.4 114.7 (+1.2) 2002.03 179.5 98.4 113.4 (-1.3) 2002.04 189.8 120.4 (109.7 predicted, -3.7) 2002.05 178.4 120.8 (105.9 predicted, -3.8) 2002.06 148.7 88.5 (101.4 predicted, -4.5) 2002.07 173.5 99.9 (96.5 predicted, -4.9) 2002.08 183.6 116.4 (92.5 predicted, -4.0) 2002.09 175.8 109.3 (88.7 predicted, -3.8) 2002.10 153.1 (1) 30.2 (2) (84.6 predicted, -4.1) 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]