Solar Terrestrial Activity Report [Image] Last update May 14, 2002 at 04:10 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 13. Solar wind speed ranged between 396 and 483 km/sec. A brief and strong southward swing of the interplanetary magnetic field has caused a significant increase in geomagnetic activity early on May 14. The IMF is, at the time I write this, weakly to moderately southwards. No solar wind shock has been observed. Solar flare activity was low. Solar flux was 172.0, the planetary A index was 12 (3-hour K indices: 4322 3332, Boulder K indices: 4232 2311). Region 9933 rotated quietly over the northwest limb. Region 9934 decayed further and lost its magnetic delta structure. The region is rotating out of view at the southwest limb. There is still a chance of an M class flare. Region 9937 decayed quickly and had only a few small spots left by the end of the day. The region could become spotless today. Region 9940 decayed further and was spotless by late afternoon. Region 9945 lost some of its small spots and was otherwise mostly unchanged and quiet. An M class flare is possible. Region 9946 decayed and had only a few small spots left by the end of the day. The region could become spotless later today. Region 9948 decayed slowly. The bright plage that had been visible near the trailing spots just one day ago decayed and returned to normal intensity. An M class flare is possible. Region 9949 decayed and had lost all but two small spots by the end of the day. The region could become spotless later today. Region 9950 decayed losing several of its small trailing spots. Region 9951 was quiet and stable. Region 9952 emerged briefly in the southwest quadrant, no spots are visible early on May 14. Flares and CMEs A total of 7 C class events were recorded on May 13. Region 9934 produced a C3.9 flare at 01:01 UTC. Region 9946 generated a C1.1 flare at 02:37 UTC. Region 9948 was the source of a C1.8 flare at 03:42 UTC, while region 9945 managed a C1.5 flare at 05:07 and a C2.3 flare at 16:41 UTC. The background x-ray flux is at the class B7 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to minor storm on May 14 and quiet to unsettled on May 15-16. 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 9933 2002.05.01 1 N18W92 0040 HSX 9934 2002.05.01 8 S16W84 0700 DKI 9937 2002.05.03 9 S07W64 0090 DSO area too large too many spots 9938 2002.05.03 S06W60 plage 9940 2002.05.04 3 N19W51 0010 BXO 9942 2002.05.05 N21W68 plage 9943 2002.05.05 S10W42 plage 9944 2002.05.07 N08W43 plage 9945 2002.05.07 11 S04W12 0260 CAO 9946 2002.05.08 4 S05W02 0030 CSO 9947 2002.05.10 N23W85 plage 9948 2002.05.10 5 S22E38 0360 EKO 9949 2002.05.11 4 S16W34 0030 CSO 9950 2002.05.11 9 S06E18 0100 DAO area too large 9951 2002.05.12 1 N10E55 0020 AXX classification should be HSX 9952 2002.05.13 3 S15W22 0000 AXX now spotless Total number of sunspots: 58 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) 2002.05 182.2 (1) 95.7 (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]