Solar Terrestrial Activity Report [Image] Last update January 27, 2001 at 08:15 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 active on January 26. Solar wind speed ranged between 316 and 380 km/sec. Solar flare activity was moderate. Solar flux was 165.6, the planetary A index was 10 (3-hour K indices: 2243 2223, Boulder K indices: 1242 2222). Region 9313 decayed slowly and produced a few flares. A minor M class flare is possible. Region 9316 was quiet and stable, C class flaring is possible. Region 9320 was spotless all day in all available images, still SEC claims the region had one spot. Region 9321 developed slowly and could produce an M class flare. Region 9322 was quiet and stable. Region 9323 had a couple of spots early in the day but was spotless by noon. Region 9324 decayed and could become spotless today. Region 9325 surprisingly managed to produce a minor M class flare. The region is more complex in magnetograms than the current spot situation indicates and further energetic flares are possible. New region 9326 emerged in the northwest quadrant. A new region has emerged to the northeast of region 9325 and there is an active region about to rotate into view at the southeast limb. Flares and CMEs A total of 5 C and 1 M class events were recorded on January 26. Region 9325 produced an M1.0/1B flare at 06:07 UT. A moderate type II sweep was recorded and a CME was noted off the east limb. Region 9313 generated a C1.3 flare at 08:56 and a C2.4 flare at 20:12 UT. Region 9320 was the source of a C1.6 flare at 12:06 UT with an associated moderate type II sweep and a CME above the southwest limb. 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 due to CMEs from other sources earlier in the day. 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, this coronal hole has been closing slowly and could disappear completely before it reaches the central meridian. Forecast The geomagnetic field is expected to be quiet to unsettled on January 27-28. 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 region numbered sunspots at AreaClassification Comment midnight 9312 2001.01.16 N06W71 plage 9313 2001.01.18 20 S07W40 0140 ESO beta-gamma 9315 2001.01.19 S28W48 plage 9316 2001.01.19 9 S17W16 0060 CAO 9318 2001.01.20 S04W74 plage 9320 2001.01.21 1 S25W61 0000 AXX (actually spotless) 9321 2001.01.21 23 S04E03 0250 DAO beta-gamma 9322 2001.01.23 5 S22W44 0040 CSO 9323 2001.01.23 4 S29W34 0020 CRO (now spotless) 9324 2001.01.23 2 N10E02 0000 BXO 9325 2001.01.25 2 N10E50 0050 HSX 9326 2001.01.26 1 N27W27 0020 CSO Total number of sunspots: 67 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) 121.5 (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]