Solar Terrestrial Activity Report [Image] Last update February 28, 2001 at 04:45 UT. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update February 2, 2001) - Did cycle 23 peak in April 2000?] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update February 2, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update February 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 February 27. Solar wind speed ranged between 335 and 427 km/sec. Solar flare activity was low. Solar flux was 130.6, the planetary A index was 13 (3-hour K indices: 3443 3211, Boulder K indices: 3343 3111). Region 9358 was quiet and decayed slowly. Region 9359 decayed and was mostly quiet. Region 9360 was quiet and in slow decay. New region 9363 emerged in the southwest quadrant, however, the region was spotted only a few hours and was spotless by early evening. Flares and CMEs A total of 2 C class events were recorded on February 27. Region 9359 produced a C1.3 flare at 10:08 UT. The background x-ray flux is at the class B2 level. Coronal holes A trans equatorial coronal hole will rotate into a geoeffective position on March 3. Forecast The geomagnetic field is expected to be quiet to unsettled on February 28 and March 1. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is fair to 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 AreaClassification Comment 9352 2001.02.15 S21W87 9355 2001.02.18 N20W83 plage 9357 2001.02.18 S24W84 plage 9358 2001.02.18 3 S10W75 0020 CSO 9359 2001.02.20 40 N13W18 0160 EAI 9360 2001.02.21 3 S10W23 0010 CRO 9361 2001.02.22 S15W62 plage 9362 2001.02.25 S07W14 plage 9363 2001.02.27 4 S20W15 0010 BXO now spotless Total number of sunspots: 50 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) 2000.02 174.1 112.9 116.8 (+3.9) 2000.03 208.2 138.5 119.9 (+3.1) 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) 2000.07 202.3 170.1 119.8 (+1.1) 2000.08 163.0 130.5 (119.5 predicted, -0.3) 2000.09 182.1 109.7 (117.9 predicted, -1.6) 2000.10 167.4 100.1 (116.3 predicted, -1.6) 2000.11 178.8 106.5 (114.4 predicted, -1.9) 2000.12 173.6 104.5 (111.8 predicted, -2.6) 2001.01 166.6 95.7 (108.2 predicted, -3.6) 2001.02 147.2 (1) 127.9 (2) 1) Running average based on the daily 20:00 UT solar flux value at 2800 MHz. 2) Unofficial, accumulated value based on the Boulder (SEC/NOAA) sunspot number. The official international sunspot number 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]