Solar Terrestrial Activity Report [Image] Last update January 28, 2001 at 05:15 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 on January 27. Solar wind speed ranged between 310 and 358 km/sec. Solar flare activity was low. Solar flux was 166.8, the planetary A index was 4 (3-hour K indices: 2210 1221, Boulder K indices: 2310 1201). Region 9313 decayed slowly and was mostly quiet. Region 9316 decayed slowly and was quiet. Region 9321 was mostly unchanged and could produce a minor M class flare. Region 9322 was quiet and stable. Region 9325 developed slowly and could produce C class flares. Region 9326 developed slowly and was quiet. New region 9327 emerged to the northeast of region 9325. A new region emerged in the northwest quadrant just north of region 9313, oddly this region was not numbered by SEC/NOAA. Flares and CMEs A total of 8 C class events were recorded on January 27. Region 9325 produced a C1.6 flare at 05:57 UT. Region 9321 generated a C1.2 flare at 07:51 UTC. 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 in progress from other sources. 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 28-30. 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 9312 2001.01.16 N06W84 plage 9313 2001.01.18 13 S06W52 0120 DAI beta-gamma 9315 2001.01.19 S28W61 plage 9316 2001.01.19 5 S16W29 0040 DAO 9318 2001.01.20 S04W87 plage 9320 2001.01.21 S25W74 plage 9321 2001.01.21 28 S05W10 0250 DAI 9322 2001.01.23 5 S22W56 0050 DSO 9323 2001.01.23 S29W47 plage 9324 2001.01.23 N10W11 plage 9325 2001.01.25 6 N11E37 0060 DSO 9326 2001.01.26 5 N27W40 0050 DSO 9327 2001.01.27 2 N17E47 0010 BXO Total number of sunspots: 64 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) 125.8 (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]