Solar Terrestrial Activity Report [Image] Last update June 26, 2001 at 03:25 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update June 3, 2001)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update June 4, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update June 4, 2001)] [Historical solar and geomagnetic data charts 1954-2001 (last update April 8, 2001)] Recent development The geomagnetic field was quiet to unsettled on June 25. Solar wind speed ranged between 441 and 573 km/sec. Solar flare activity was low. Solar flux was 182.4, the planetary A index was 8 (3-hour K indices: 2223 2322, Boulder K indices: 2322 1222). Region 9503 rotated off the visible disk displaying moderate activity, an M class flare from behind the west limb is possible. Region 9504 is rotating quietly off the visible disk. Region 9506 was mostly quiet and stable. Region 9509 decayed into spotless plage. Region 9511 became somewhat more complex again with intermixing occurring in the central part of the region. A minor M class flare is possible. Region 9512 was decaying late in the day and had otherwise been quiet. Minor M class flares are possible. Region 9513 developed slowly and quietly. The region may be capable of producing M class flares. Region 9514 was quiet and stable. Region 9515 appeared to be in slow decay be the end of the day. Region 9516 was quiet and stable. New region 9517 emerged near the southwest limb. Flares and CMEs A total of 7 C class events were recorded on June 25. Region 9503 produced a C3.1 flare at 00:27 UTC. The remainder of the flares were optically uncorrelated. June 24: A full halo CME was observed at 08:18 UTC in LASCO C3 images. A C3.9 flare in region 9511, then at the center of the solar disk, may have been associated with the CME. There is, however, a greater likelihood that the CME had a backside origin. The background x-ray flux is at the class B8 level. Coronal holes A coronal hole to the south of region 9511 was in a geoeffective position on June 24. Forecast The geomagnetic field is expected to be quiet to unsettled on June 26 and quiet to active on June 27-28. 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 Area Classification Comment 9503 2001.06.13 7 N16W86 0140 DSO beta-gamma 9504 2001.06.13 1 N08W83 0220 HSX 9505 2001.06.14 N21W73 plage 9506 2001.06.14 6 N17W61 0180 CAO 9509 2001.06.19 S10W89 plage 9511 2001.06.20 21 N09W14 0100 DAO beta-gamma 9512 2001.06.21 31 S24W23 0190 EAI beta-gamma 9513 2001.06.21 31 N22E31 0200 FAI 9514 2001.06.22 1 N17E28 0030 HSX 9515 2001.06.23 17 S07E19 0130 DAO 9516 2001.06.23 2 N12E42 0100 CSO 9517 2001.06.25 3 S15W59 0030 BXO Total number of sunspots: 120 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 2000.03 208.2 138.5 119.9 (+3.1) 2000.04 184.2 125.5 120.8 (+0.9) cycle 23 sunspot max. 2000.05 184.9 121.6 119.0 (-1.8) 2000.06 179.8 124.9 118.7 (-0.3) 2000.07 202.3 170.1 119.7 (+1.0) 2000.08 163.0 130.5 118.6 (-1.1) 2000.09 182.1 109.7 116.2 (-2.4) 2000.10 167.4 99.4 114.5 (-1.7) 2000.11 178.8 106.8 112.8 (-1.7) 2000.12 173.6 104.4 (111.1 predicted, -1.7) 2001.01 166.6 95.6 (107.6 predicted, -3.5) 2001.02 146.6 80.6 (102.8 predicted, -4.8) 2001.03 177.7 113.5 (99.2 predicted, -3.6) 2001.04 177.7 108.2 (98.0 predicted, -1.2) 2001.05 147.1 97.3 (97.3 predicted, -0.7) 2001.06 178.3 (1) 172.7 (2) (94.6 predicted, -2.7) 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. ------------------------------------------------------------------------ Do you know about the survey which will be held this Summer among the listeners of WWV and WWVH? There is information about this survey at 16 minutes past the hour on WWV and at 47 minutes past the hour on WWVH. If you want to participate send an email with your name and address. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]