Solar Terrestrial Activity Report [Image] Last update August 7, 2002 at 05:55 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update August 7, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update August 7, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update August 7, 2002)] [Historical solar and geomagnetic data charts 1954-2002 (last update April 13, 2002)] Recent development The geomagnetic field was quiet to unsettled on August 6. Solar wind speed ranged between 358 and 415 km/sec. Solar flare activity was low. Solar flux was 144.6, the planetary A index was 9 (3-hour planetary K indices: 3312 2331, Boulder K indices: 2211 2112). Region 10051 was quiet and stable, as was region 10055. Region 10057 decayed slowly and lost some intermediate and leading spots. Slow development was observed in the trailing spot section. A minor M class flare remains a possibility. Region 10058 developed slowly and quietly. Region 10059 was mostly quiet and unchanged. Region 10061 developed quite a few new spots and currently has a magnetic delta in the intermediate spot section. M class flares are possible. New region 0063 rotated into view at the northeast limb. It's too early to be certain, however, the region appears to have a magnetic delta structure and may be capable of producing another M class flare. A new region emerged due north of the trailing spots in region 10059 but has not yet been numbered by SEC/NOAA. Flares and CMEs A total of 8 C class events was recorded on August 6. Region 10057 produced a C8.3/1F flare at 01:44, a C4.3 flare at 11:31 and a C7.6 flare at 15:27 UTC. Region 10061 generated a C2.8 flare at 12:12 and a C3.3 flare at 12:31 UTC. Region 10063 was the source of a C7.9/1N flare at 12:58 UTC. A filament in the southwest quadrant erupted between 16 and 18h UTC and was associated with a CME observed over a large part of the southern hemisphere limbs. The CME was probably not geoeffective. The background x-ray flux is at the class B6 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 active, possibly with a few isolated minor storm intervals, on August 7-8 due to a coronal stream. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is 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 10051 2002.07.27 1 S14W65 0060 HSX 10054 2002.07.28 S22W53 plage 10055 2002.07.29 2 N14W29 0020 HSX 10056 2002.07.31 N05W30 plage 10057 2002.08.01 15 S07W66 0340 EAI beta-gamma 10058 2002.08.01 7 S06E03 0040 CSO 10059 2002.08.02 10 N13E14 0060 CSO 10060 2002.08.03 S27W65 plage 10061 2002.08.03 27 N08E41 0280 EAI beta-gamma-delta 10062 2002.08.05 S05W36 plage 10063 2002.08.06 3 N15E75 0110 ESO beta-delta? Total number of sunspots: 65 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) 2002.08 163.0 (1) 37.0 (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]