Solar Terrestrial Activity Report [Image] Last update February 8, 2001 at 05:00 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) - Cycle 23 peaked 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 unsettled on February 7. Solar wind speed ranged between 419 and 561 km/sec under the influence of a weakening coronal stream. Solar flare activity was low. Solar flux was 164.0, the planetary A index was 5 (3-hour K indices: 2311 1222, Boulder K indices: 2311 1211). Region 9330 was quiet and stable. Region 9334 was quiet but could produce C and minor M class flares. Region 9335 was mostly unchanged and could generate a minor M class flare. Regions 9337 and 9338 were quiet and stable. Region 9339 was quiet and stable and could produce a minor M class flare. Region 9341 was quiet and stable. Region 9342 was spotless most of the day. New region 9343 emerged in the northeast quadrant near the center of the solar disk, then decayed into spotless plage. Flares and CMEs Only 1 C class event was recorded on February 7, it was an optically uncorrelated C1.0 flare at 00:48 UT. The background x-ray flux is at the class B4 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to unsettled February 8-10. 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 9329 2001.01.29 S09W66 plage 9330 2001.01.30 8 N25W36 0080 DAO 9331 2001.01.30 N13W78 plage 9332 2001.01.30 N09W84 plage 9334 2001.02.01 21 N12W01 0150 EAO 9335 2001.02.03 15 N10E14 0100 EAO 9336 2001.02.03 S09W54 plage 9337 2001.02.03 7 S27E25 0060 DAO 9338 2001.02.04 6 S19E24 0020 BXO 9339 2001.02.04 12 S09E34 0240 EAO 9340 2001.02.05 S13W21 plage 9341 2001.02.06 2 S08E09 0010 CRO 9342 2001.02.06 1 S26E42 0000 AXX 9343 2001.02.07 1 N03E08 0000 AXX 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) 2000.02 174.1 112.9 116.8 (+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 (119.7 predicted, -0.1) 2000.09 182.1 109.7 (118.4 predicted, -1.3) 2000.10 167.4 100.1 (116.7 predicted, -1.7) 2000.11 178.8 106.5 (114.8 predicted, -1.9) 2000.12 173.6 104.5 (112.2 predicted, -2.6) 2001.01 166.6 95.7 (108.7 predicted, -3.5) 2001.02 162.6 (1) 37.3 (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]