Solar Terrestrial Activity Report [Image] Last update January 29, 2001 at 02:15 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 unsettled on January 28. Solar wind speed ranged between 300 and 375 km/sec. A minor disturbance began after noon when the interplanetary magnetic field swung moderately southwards. Only a minor solar wind speed increase was observed for the remainder of the day. The source of the disturbance is uncertain. Active and even minor storm intervals are possible today. Solar flare activity was moderate. Solar flux was 167.6, the planetary A index was 6 (3-hour K indices: 0112 3223, Boulder K indices: 0112 4223). Region 9313 decayed further and was at the center of an interesting long duration proton producing event. Region 9316 decayed fairly quickly and could become spotless today. Region 9321 was mostly unchanged and could produce a minor M class flare. Region 9322 was quiet and stable. Region 9325 was mostly quiet and stable, C class flares are possible. Region 9326 decayed slowly and was quiet. Region 9327 decayed and was spotless by noon. New region 9328 in the northwest quadrant was finally numbered, the region is already decaying. An active region behind the northeast limb will probably rotate into view within 2-3 days. Flares and CMEs A total of 3 C and 1 M class events were recorded on January 28. Region 9321 produced a C1.0 flare at 07:11 UT. Region 9313 was the source of a long duration M1.5/1N event peaking at 16:00 UT. This event was the source of an increase in proton fluxes with the above 50 MeV flux peaking at 1.9 pfu and the above 10 MeV flux so far having reached 27 pfu. A wide and fast full halo CME was observed as well and the CME will likely reach Earth sometime between late on January 30 and noon on January 31. January 26: A long duration C1.3 event began in LASCO EIT images at 15:48 UT and peaked at 17:52. The source was a filament (prominence) eruption in the northern hemisphere above the central meridian and into the northwest quadrant. There may have been a geoeffective CME produced by this event, but it was difficult to observe because of CMEs from other sources already in progress. The background x-ray flux is at the class B6 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 29-31. 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 9313 2001.01.18 7 S04W65 0030 CSO 9315 2001.01.19 S28W74 plage 9316 2001.01.19 1 S14W44 0000 AXX 9320 2001.01.21 S25W87 plage 9321 2001.01.21 20 S04W24 0300 DAO 9322 2001.01.23 2 S22W68 0010 AXX 9323 2001.01.23 S29W60 plage 9324 2001.01.23 N10W24 plage 9325 2001.01.25 6 N10E25 0050 CSO 9326 2001.01.26 3 N28W53 0040 CSO 9327 2001.01.27 2 N14E32 0000 BXO 9328 2001.01.28 3 N06W58 0040 DAO Total number of sunspots: 44 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) 129.8 (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]