Solar Terrestrial Activity Report [Image] Last update January 26, 2001 at 04:35 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 on January 25. Solar wind speed ranged between 331 and 430 km/sec. Solar flare activity was low. Solar flux was 168.6, the planetary A index was 4 (3-hour K indices: 1001 1221, Boulder K indices: 2010 1321). Region 9311 continued to be a frequent flare producer as the region rotated over the west limb. Region 9313 was mostly quiet and stable. The region could produce a minor M class flare. Region 9316 was quiet and stable, C class flaring is possible. Region 9320 was quiet and stable, the region is spotless early on Jan.26. Region 9321 was mostly quiet and stable but could produce C flares and perhaps a minor M class flare. Regions 9322, 9323 and 9324 were quiet and stable. New region 9325 rotated into view at the northeast limb. Flares and CMEs A total of 15 C class events were recorded on January 25. Region 9313 produced a C1.4 flare at 14:07 UT. Region 9311 generated a C1.1 flare at 12:20 and was the likely source of most of the optically uncorrelated flares, including a C7.4 flare at 07:13, a C4.0 flare at 08:23 and a C4.2 flare at 08:54 UT. The background x-ray flux is at the class B6 level. Coronal holes A small coronal hole in the northern hemisphere will rotate into a geoeffective position on January 28. Forecast The geomagnetic field is expected to be quiet to unsettled on January 26-28. 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 9311 2001.01.15 2 N05W86 0060 HSX 9312 2001.01.16 N06W58 plage 9313 2001.01.18 27 S07W27 0130 EAI beta-gamma 9315 2001.01.19 S28W35 plage 9316 2001.01.19 10 S16W03 0080 CAO 9318 2001.01.20 S04W61 plage 9320 2001.01.21 1 S24W50 0000 AXX 9321 2001.01.21 19 S05E16 0160 DAO 9322 2001.01.23 4 S22W32 0040 HSX 9323 2001.01.23 3 S28W23 0010 CRO 9324 2001.01.23 3 N10E16 0010 BXO 9325 2001.01.25 4 N10E64 0050 CSO Total number of sunspots: 73 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) 2001.01 167.5 (1) 116.4 (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]