Solar Terrestrial Activity Report [Image] Last update August 5, 2002 at 09:35 UTC. No updates could be posted on August 4 and early on August 5 as both my main and backup Internet connections were unavailable. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update July 1, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update July 1, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update July 1, 2002)] [Historical solar and geomagnetic data charts 1954-2002 (last update April 13, 2002)] Recent development The geomagnetic field was quiet to minor storm on August 4. Solar wind speed ranged between 406 and 482 km/sec. Solar flare activity was moderate. Solar flux was 150.9, the planetary A index was 16 (3-hour planetary K indices: 4543 2231, Boulder K indices: 4532 2221). Region 10050 decayed and rotated over the southwest limb. Region 10051 was quiet and stable. Region 10055 decayed slowly and lost its trailing spots. Region 10057 developed slowly and could produce minor M class flares. Region 10058 decayed slowly and quietly. Region 10059 was mostly unchanged and quiet. Region 10060 decayed quickly and had only a couple of tiny spots left by midnight. Region 10061 was quiet and stable. Flares and CMEs A total of 8 C and 1 M class events was recorded on August 4. None of the events were optically correlated, however, most are thought to have had their origin at and slightly behind the west limb. This includes a major long duration M6.6 event peaking at 09:55 UTC, as well as a C7.4 flare at 07:20 and a C6.9 flare at 14:18 UTC. The background x-ray flux is at the class B8 level. Coronal holes A coronal hole in the southern hemisphere was in a geoeffective position on August 3-4. Forecast The geomagnetic field is expected to be quiet to unsettled on August 5 and quiet to active, possibly with a few isolated minor storm intervals, on August 6-7 due to a coronal stream. 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 no. Location at region numbered sunspots midnight Area Classification Comment 10048 2002.07.26 N21W64 plage 10050 2002.07.26 7 S08W87 0420 FHO 10051 2002.07.27 1 S15W38 0090 HSX 10052 2002.07.28 N09W76 plage 10053 2002.07.28 S17W67 plage 10054 2002.07.28 S22W27 plage 10055 2002.07.29 4 N13W01 0040 DAO 10056 2002.07.31 N05W04 plage 10057 2002.08.01 33 S08W39 0380 EAC beta-gamma 10058 2002.08.01 1 S07E28 0030 HSX 10059 2002.08.02 12 N15E41 0120 DAO 10060 2002.08.03 5 S28W41 0040 DRO 10061 2002.08.03 7 N08E65 0190 DAO Total number of sunspots: 70 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 2001.07 131.3 81.8 111.7 (+1.9) 2001.08 162.9 106.4 113.6 (+1.8) 2001.09 233.2 150.7 114.1 (+0.5) 2001.10 207.6 125.5 114.0 (-0.1) 2001.11 210.6 106.5 115.5 (+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 (113.1 predicted, -0.4) 2002.03 179.5 98.4 (108.7 predicted, -4.4) 2002.04 189.8 120.4 (102.8 predicted, -5.9) 2002.05 178.4 120.8 (98.3 predicted, -4.5) 2002.06 148.7 88.5 (93.8 predicted, -4.5) 2002.07 173.5 99.9 (89.0 predicted, -4.8) 2002.08 172.9 (1) 28.0 (2) (84.9 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]