Solar Terrestrial Activity Report [Image] Last update February 5, 2002 at 03:15 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update February 2, 2002)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update February 2, 2002)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update February 2, 2002)] [Historical solar and geomagnetic data charts 1954-2001 (last update January 12, 2002)] Recent development The geomagnetic field was quiet to unsettled on February 4. Solar wind speed ranged between 315 and 372 km/sec. Solar flare activity was moderate. Solar flux was 234.6, the planetary A index was 6 (3-hour K indices: 1100 2333, Boulder K indices: 1210 3323). Region 9800 decayed slowly and quietly. Minor M class flares are still possible. Region 9801 was mostly quiet and stable. Region 9802 decayed with the larger penumbras fragmenting. A weak magnetic delta structure remains and the region could still produce M class flares. Region 9806 decayed slowly and quietly. Region 9807 has many small spots and appears to be slowly decaying. Region 9808 was quiet and stable. Region 9809 unexpectedly produced a couple of event level flares early in the day and was otherwise quiet. Regions 9810, 9811 and 9812 were quiet and stable. Region 9813 was spotless all day in all available images. Region 9814 was quiet and stable, as was region 9815. New region 9816 emerged rapidly near region 9802 and may be capable of minor M class flare production. Flares and CMEs A total of 4 C and 3 M class events were recorded on February 4. Region 9801 produced a C7.3 flare at 02:00 UTC. Region 9802 generated a C6 flare at 02:11, a C2.7 flare at 10:24, a C7.8 flare at 19:09 and an M1.3 flare at 23:30 UTC. Region 9809 was the source of an M2.3 flare at 06:02 and an M1.5 flare at 06:58 UTC. The background x-ray flux is at the class C1 level. Coronal holes A well defined trans equatorial coronal hole was in a geoeffective position on February 3. Forecast The geomagnetic field is expected to be quiet to active on February 5. A coronal stream is likely to cause unsettled to active geomagnetic conditions on February 6-7, possibly with a few minor storm intervals as well. 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 9800 2002.01.25 5 N10W73 0250 DAO 9801 2002.01.25 1 S04W54 0080 HSX 9802 2002.01.26 57 S14W44 0640 FKI beta-gamma-delta 9804 2002.01.28 S17W65 plage 9805 2002.01.28 N14W26 plage 9806 2002.01.28 3 N12W21 0030 CSO 9807 2002.01.30 27 S27E13 0090 EAI 9808 2002.01.31 7 N17E02 0050 DSO 9809 2002.01.31 6 S06E16 0100 DSO 9810 2002.02.01 4 N09E42 0230 DAO 9811 2002.02.02 7 S28E57 0290 DAO 9812 2002.02.02 4 N12W42 0030 DRO 9813 2002.02.03 1 S24W26 0010 AXX actually spotless 9814 2002.02.03 1 N07E02 0010 HRX 9815 2002.02.03 2 N10E57 0080 HAX 9816 2002.02.04 9 S13W33 0080 DAO Total number of sunspots: 134 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 2000.12 173.6 104.4 112.0 (-0.7) 2001.01 166.6 95.6 108.7 (-3.3) 2001.02 146.6 80.6 104.1 (-4.6) 2001.03 177.7 113.5 104.8 (+0.7) 2001.04 177.7 107.7 107.6 (+2.8) 2001.05 147.1 96.6 108.7 (+1.1) 2001.06 173.0 134.0 109.8 (+1.1) 2001.07 131.3 82.2 111.7 (+1.9) 2001.08 162.9 106.8 (113.5 predicted, +1.8) 2001.09 233.2 150.7 (113.3 predicted, -0.2) 2001.10 207.6 125.6 (111.0 predicted, -2.3) 2001.11 210.6 106.5 (109.6 predicted, -1.4) 2001.12 235.1 131.8 (106.2 predicted, -3.4) 2002.01 226.6 113.9 (102.6 predicted, -3.6) 2002.02 238.4 (1) 36.6 (2) (101.2 predicted, -1.4) 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 25-40% 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 noted in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News]