Solar Terrestrial Activity Report [Image] Last update May 7, 2002 at 04:05 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 3, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update May 3, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update May 3, 2002)] [Historical solar and geomagnetic data charts 1954-2002 (last update April 13, 2002)] Recent development The geomagnetic field was quiet to active on May 6. Solar wind speed ranged between 297 and 392 km/sec, increasing after 13h UTC due to the influence of a fairly slow coronal stream. Solar flare activity was low. Solar flux was 190.8, the planetary A index was 11 (3-hour K indices: 2113 3433, Boulder K indices: 1112 3423). Region 9928 decayed further and could become spotless within a couple of days. Region 9929 developed slowly and quietly. Region 9931 decayed slowly and quietly. Region 9932 decayed slowly and was quiet. Region 9933 was quiet and stable. Region 9934 developed some new spots (and may have redeveloped a weak magnetic delta structure) and remains capable of M class flare production. Region 9935 was spotless most of the day. Region 9936 decayed slowly and could soon become spotless. Region 9937 decayed slowly and was mostly quiet. Regions 9938, 9939 and 9940 were quiet and stable. Region 9941 decayed slowly and quietly. Region 9942 decayed and could become spotless today. Region 9943 decayed and was spotless by the end of the day. Several new regions are visible early on May 7. A region began to rotate into view at the southeast limb at noon on May 6 by was not numbered by SEC/NOAA. A new region is emerging in the northeast quadrant just southeast of region 9940. Another new region is emerging to the east of region 9933. Flares and CMEs A total of 5 C class events were recorded on May 6. Region 9935 produced a C1.7 long duration event peaking at 14:05 UTC. A long duration C6.7 event began at 23:35 UTC and peaked at 00:11 on May 7. The source of this event appears to have been an erupting prominence. An M1.4 flare was observed at 03:46 UTC on May 7. As I write this I haven't been able to confirm the exact location of the flare. A full halo CME was observed in LASCO C3 images beginning at 14:18 UTC on May 6 at the east limb. Its source was likely well behind the east limb. 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 unsettled on May 7-9. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is fair to 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 9927 2002.04.29 S28W26 plage 9928 2002.04.29 8 N18W18 0050 CSO 9929 2002.04.30 5 N23W66 0170 DAO 9930 2002.05.01 N12W83 plage 9931 2002.05.01 3 N16W50 0050 CSO 9932 2002.05.01 10 S28W08 0070 ESO 9933 2002.05.01 1 N18E00 0100 HSX 9934 2002.05.01 23 S17E08 0500 EKI beta-gamma 9935 2002.05.02 1 S19W23 0000 AXX now spotless 9936 2002.05.02 5 S16W13 0020 CSO 9937 2002.05.03 9 S10E29 0180 DKO 9938 2002.05.03 1 S05E32 0030 HAX 9939 2002.05.04 1 N17E40 0040 HSX 9940 2002.05.04 1 N13E42 0040 HAX 9941 2002.05.05 6 S22W03 0040 DSO 9942 2002.05.05 1 N21E21 0010 CSO 9943 2002.05.05 1 S11E50 0020 HSX now spotless Total number of sunspots: 76 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 2001.04 177.7 107.7 107.5 (+2.7) 2001.05 147.1 96.6 108.6 (+1.1) 2001.06 173.0 134.0 109.8 (+1.2) 2001.07 131.3 82.2 111.7 (+1.9) 2001.08 162.9 106.8 113.6 (+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 (114.7 predicted, +0.7) 2001.12 235.1 132.2 (112.5 predicted, -2.2) 2002.01 226.6 113.9 (109.8 predicted, -2.7) 2002.02 205.0 108.0 (108.4 predicted, -1.4) 2002.03 179.5 98.1 (104.2 predicted, -4.2) 2002.04 189.8 120.4 (98.3 predicted, -3.9) 2002.05 178.5 (1) 45.5 (2) (93.8 predicted, -4.5) 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]