Solar Terrestrial Activity Report [Image] Last update January 25, 2001 at 04:55 UT. [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 minor storm on January 24. Solar wind speed ranged between 375 and 493 km/sec. Solar flare activity was moderate. Solar flux was 172.5, the planetary A index was 18 (3-hour K indices: 2314 5443, Boulder K indices: 2314 4433). Region 9311 developed further and produced many flares. Further C class flaring is likely to continue today as the region rotates off the visible disk. Another M class flare is possible. Region 9313 developed slowly and was mostly quiet. The region could produce a minor M class flare. Region 9316 was quiet and stable, C class flaring is possible. Region 9319 was mostly quiet and stable, the region has rotated over the west limb. Region 9320 was quiet and stable. Region 9321 developed slowly and could produce C flares and perhaps a minor M class flare. Regions 9322, 9323 and 9324 were quiet and stable. An active region is rotating into view at the northeast limb. Flares and CMEs A total of 12 C and 1 M class events were recorded on January 24. Region 9311 produced a C9.2/1F flare at 00:49, a C1.3 flare at 08:18, an M1.0/2F flare at 14:47 (perhaps related to a partial halo CME observed off the west limb, the north and south pole), a C6.3 flare at 15:51, a C4.5 flare at 18:34 and a C1.4 flare at 20:48 UT. Region 9321 generated a C1.8 flare at 07:27 UT. 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 unsettled on January 25-26. 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 region numbered sunspots at Area Classification Comment midnight 9310 2001.01.14 N27W80 plage 9311 2001.01.15 9 N06W76 0230 EAO beta-gamma 9312 2001.01.16 N06W45 plage 9313 2001.01.18 34 S07W12 0130 DAI beta-gamma 9315 2001.01.19 S28W22 plage 9316 2001.01.19 9 S15E11 0100 CAO 9318 2001.01.20 S04W48 plage 9319 2001.01.21 1 S18W89 0010 AXX 9320 2001.01.21 4 S23W39 0030 BXO 9321 2001.01.21 24 S06E31 0180 DAI beta-gamma? 9322 2001.01.23 7 S22W16 0020 CRO 9323 2001.01.23 4 S28W10 0020 DAO 9324 2001.01.23 4 N09E29 0030 CSO Total number of sunspots: 96 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) 2001.01 167.4 (1) 111.2 (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]