Solar Terrestrial Activity Report [Image] Last update November 1, 2000 at 04:55 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update October 2, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update October 2, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update October 2, 2000)] [Historical solar and geomagnetic data charts 1954-2000 (last update October 20, 2000)] Recent development The geomagnetic field was quiet to active on October 31. Solar wind speed ranged between 340 and 501 km/sec. A moderate solar wind shock was observed at ACE at 16:30 UTC. The interplanetary magnetic field was moderately southward for the first hours after the shock passage, then weakened and is currently mostly northwards. The geomagnetic field was initially active and is now quiet to unsettled. The CME may have been the one associated with the M4 flare on October 29, in that case it was less impressive than expected. Solar flare activity was low. Solar flux was 193.4, the planetary A index was 11 (3-hour K indices: 3223 2433, Boulder K indices: 3323 3423). Region 9206 was quiet and in slow decay. Region 9208 decayed slowly and could become spotless today. Region 9209 lost almost half of its spots but may still be capable of producing a minor M class flare. Region 9210 was quiet and stable. Region 9212 decayed early in the day, however, early on November 1 the region appears to have become more complex and could, together with region 9213, produce a major flare. Region 9213 was quiet and stable but could produce occasional C and minor M class flares. Region 9214 did not change much and is still capable of minor M class flare production. Oddly, a spotted region rotating into view at the northeast limb was not numbered by SEC/NOAA. Flares and CMEs A total of 4 C class events were recorded on October 31. Region 9209 produced a C2.1 flare at 00:10, a C6.0/1F flare at 03:00 and a C2.0 flare at 19:58 UTC. Spotless region 9207 generated a C1.6 flare at 09:02 UTC. The background x-ray flux is at the class B8 level. Coronal holes A coronal hole in the northern hemisphere will rotate into a geoeffective position on November 3. Forecast The geomagnetic field is expected to be quiet to active on November 1. 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 no. Location at region numbered sunspots midnight Area Classification Comment 9206 20001023 5 N23W45 0030 CSO 9207 20001023 S17W38 plage 9208 20001023 1 S08W30 0000 AXX 9209 20001025 16 S22W06 0200 DAI 9210 20001026 11 S28E08 0040 CSO 9212 20001028 11 N10E34 0110 DAO beta-gamma 9213 20001028 7 N02E30 0200 CAO 9214 20001028 14 S11E27 0100 EAO 9215 20001029 N20W83 plage 9216 20001029 N17W33 plage Total number of sunspots: 65 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.09 135.7 71.5 102.3 (+4.8) 1999.10 164.8 116.7 107.8 (+5.5) 1999.11 191.5 133.2 110.9 (+3.1) 1999.12 169.8 84.6 111.0 (+0.1) 2000.01 158.1 90.1 112.8 (+1.8) 2000.02 174.1 112.9 116.6 (+3.8) 2000.03 208.2 138.5 119.8 (+3.2) 2000.04 184.2 125.3 (121.0 predicted, +1.2) 2000.05 184.9 120.8 (121.3 predicted, +0.3) 2000.06 179.8 124.9 (122.8 predicted, +1.5) 2000.07 202.3 169.1 (124.9 predicted, +2.1) 2000.08 163.0 130.5 (125.0 predicted, +0.1) 2000.09 182.1 109.9 2000.10 167.4 (1) 138.9 (2) 1) Running average based on the daily 20:00 UTC solar flux value at 2800 MHz. 2) Unofficial, accumulated value. The official value is typically 25-40% 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 in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]