Solar Terrestrial Activity Report [Image] Last update February 6, 2002 at 02:20 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 active on February 5. Solar wind speed ranged between 332 and 568 km/sec. A high speed coronal stream began influencing the field as early as noon and increased in intensity throughout the latter half of the day. Early on Feb.6 solar wind speed has reached 710 km/sec. Solar flare activity was low. Solar flux was 220.6, the planetary A index was 16 (3-hour K indices: 4322 3443, Boulder K indices: 3332 3443). Region 9800 rotated quietly off the visible disk. Region 9801 was quiet and stable. Region 9802 decayed further and simplified. The region was quiet but could still produce a minor M class flare. Region 9806 was quiet and stable. Region 9807 lost some of its spots but increased its areal coverage. Region 9808 developed slowly and was mostly quiet. Region 9809 was mostly unchanged and quiet. Regions 9810, 9811 and 9812 were quiet and stable. Region 9814 was quiet and stable but could become spotless today. Region 9815 was quiet and stable. Region 9816 developed further and could produce a minor M class flare. New region 9817 emerged in the southeast quadrant. New region 9818 emerged near the northeast limb. New region 9819 rotated into view at the southeast limb. [A problem occurred on the SOHO spacecraft early on February 5 and no new images will be produced until the spacecraft resumes normal operation.] Flares and CMEs A total of 4 C class events were recorded on February 5. Region 9816 produced a C2.2 flare at 08:37 UTC. Region 9809 generated a C4.4/1F flare at 20:13 UTC. Region 9808 was the source of a C3.0 flare at 22:33 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 unsettled to active on February 6-7 with a chance of a few minor storm intervals. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is 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 Location region numbered no. at Area Classification Comment sunspots midnight 9800 2002.01.25 3 N06W89 0140 DAO 9801 2002.01.25 1 S04W71 0070 HSX 9802 2002.01.26 44 S15W56 0500 EAI beta-gamma-delta 9804 2002.01.28 S17W78 plage 9805 2002.01.28 N14W39 plage 9806 2002.01.28 1 N11W36 0030 HSX 9807 2002.01.30 18 S25E01 0120 EAO 9808 2002.01.31 13 N17W13 0060 DAO 9809 2002.01.31 7 S06E03 0100 DSO 9810 2002.02.01 3 N10E26 0190 DKO 9811 2002.02.02 12 S25E45 0240 DAO 9812 2002.02.02 2 N13W57 0020 CRO 9813 2002.02.03 S24W39 plage 9814 2002.02.03 2 N07W13 0010 AXX 9815 2002.02.03 3 N12E43 0070 CAO 9816 2002.02.04 11 S12W46 0150 DSO 9817 2002.02.05 3 S07E23 0020 BXO 9818 2002.02.05 1 N06E54 0020 AXX 9819 2002.02.05 2 S29E68 0050 HSX Total number of sunspots: 126 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) 2002.02 234.7 (1) 46.8 (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]