Solar Terrestrial Activity Report [Image] Last update January 23, 2001 at 04:30 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update January 2, 2001) - Has cycle 23 peaked?] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update January 2, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update January 2, 2001)] [Historical solar and geomagnetic data charts 1954-2000 (last update January 18, 2001)] Recent development The geomagnetic field was quiet to unsettled on January 22. Solar wind speed ranged between 350 and 492 km/sec. Solar flare activity was low. Solar flux was 162.1, the planetary A index was 10 (3-hour K indices: 3322 3322, Boulder K indices: 3323 3322). Region 9311 developed slowly and was mostly quiet. Region 9313 developed slowly and could produce an isolated M class flare. Region 9316 was quiet and stable, C class flaring is possible. Region 9318 decayed into spotless plage. Region 9319 was quiet and stable, as was region 9320. Region 9321 was quiet and appears to be developing slowly. Region 9315 has reemerged early on January 23. Flares and CMEs A total of 2 C class events were recorded on January 22. Region 9313 generated a C2.7 flare at 06:49 UTC. An optically uncorrelated C2.8 flare was recorded at 22:05 UT. January 20: Region 9313 produced an M1.2/2F flare at 18:47 UT. The flare was accompanied by a strong type II sweep and a full halo coronal mass ejection. A major M7.7/2B flare was observed at 21:20 UT. This flare was accompanied by a moderate type II sweep and a large and fast coronal mass ejection. Although the main core of the CMEs will not be heading towards Earth, parts of the CMEs will begin to influence the geomagnetic field sometime on January 23. The background x-ray flux is at the class B5 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to minor storm on January 23-24. 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 9310 2001.01.14 N27W54 plage 9311 2001.01.15 7 N05W48 0100 DSO beta-gamma 9312 2001.01.16 N06W19 plage 9313 2001.01.18 19 S07E15 0190 EAI beta-gamma 9315 2001.01.19 S28E05 plage 9316 2001.01.19 6 S16E38 0130 DAO 9318 2001.01.20 S04W22 plage 9319 2001.01.21 7 S18W56 0030 DRO 9320 2001.01.21 2 S24W11 0020 DRO 9321 2001.01.21 7 S06E53 0100 DAO Total number of sunspots: 48 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.11 191.5 133.2 111.0 (+3.2) 1999.12 169.8 84.6 111.1 (+0.1) 2000.01 158.1 90.1 112.9 (+1.8) 2000.02 174.1 112.9 116.7 (+3.8) 2000.03 208.2 138.5 119.9 (+3.2) 120.8 (+0.9) 2000.04 184.2 125.5 cycle 23 peak candidate 2000.05 184.9 121.6 119.0 (-1.8) 2000.06 179.8 124.9 118.7 (-0.3) 2000.07 202.3 169.1 (120.3 predicted, +1.6) 2000.08 163.0 130.5 (120.8 predicted, +0.5) 2000.09 182.1 109.9 (119.9 predicted, -0.9) 2000.10 167.4 100.1 (118.7 predicted, -1.2) 2000.11 178.8 106.5 (116.8 predicted, -1.9) 2000.12 173.6 104.5 (114.2 predicted, -2.6) 2001.01 167.2 (1) 99.4 (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 noted in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]