Solar Terrestrial Activity Report [Image] Last update May 3, 2002 at 02:55 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 unsettled on May 2. Solar wind speed ranged between 385 and 472 km/sec under the influence of a weak coronal stream. Solar flare activity was low. Solar flux was 169.0, the planetary A index was 7 (3-hour K indices: 2202 3322, Boulder K indices: 2201 2321). Region 9919 decayed slowly and was mostly quiet. Region 9926 developed early in the day, then began to decay and had only a few small spots left early on May 3. Region 9927 decayed slowly and quietly. Region 9928 developed substantially, particularly in the northern negative magnetic polarity area. Further development is likely and the region is becoming capable of producing M class flares. Region 9929 reemerged and is developing quickly with many new spots observed early on May 3. Region 9930 decayed significantly and has only a few small spots left early on May 3. The region could, like region 9926, become spotless later today or tomorrow. Region 9931 developed slowly. The region was quiet and is likely to remain quiet with the positive and negative magnetic areas being well separated. Region 9932 developed quickly early in the day and was mostly quiet and stable later on. Region 9933 was quiet and stable. Region 9934 is a fairly complex region with magnetic delta structures within both the northern and southern large penumbra. The region was mostly quiet but could produce an M class flare any time. A major flare is possible. New region 9935 emerged in the southeast quadrant. New region 9936 emerged in the southeast quadrant late on May 1, developed slowly early on May 2 and has since decayed slowly. Flares and CMEs A total of 6 C class events were recorded on May 2. Region 9919 produced a C1.1 flare at 03:06 UTC. Region 9926 generated a C2.3 flare at 14:50 and a long duration C6.7 event peaking at 21:33 UTC. The LDE was associated with a fairly small CME observed mainly off the northwest limb. The background x-ray flux is at the class B7 level. Coronal holes A well defined coronal hole in the northern hemisphere rotated across the central meridian on May 2 but was likely too far to the north to be geoeffective. Another coronal hole, further east in the northern hemisphere, is currently poorly defined and will rotate into a geoeffective position on May 4-5. Forecast The geomagnetic field is expected to be quiet to unsettled on May 3-6. 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 Location region numbered no. at Area Classification Comment sunspots midnight 9916 2002.04.21 S15W69 plage 9917 2002.04.22 S30W85 plage 9919 2002.04.22 1 N13W54 0060 HSX 9921 2002.04.23 N14W80 plage 9922 2002.04.23 N22W64 plage 9926 2002.04.27 9 N14W42 0080 DAO 9927 2002.04.29 4 S29E27 0050 HSX 9928 2002.04.29 6 N17E35 0080 DAO beta-gamma 9929 2002.04.30 1 N21W11 0000 AXX 9930 2002.05.01 9 N12W30 0050 DRO 9931 2002.05.01 9 N16E06 0060 DAO 9932 2002.05.01 4 S28E44 0110 DAO 9933 2002.05.01 1 N17E52 0090 HSX 9934 2002.05.01 11 S18E62 0420 EAO beta-gamma-delta 9935 2002.05.02 6 S18E33 0030 CAO 9936 2002.05.02 6 S15E42 0050 DSO Total number of sunspots: 67 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) 2002.05 165.7 (1) 11.4 (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]