Solar Terrestrial Activity Report [Image] Last update June 27, 2001 at 04:00 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 active on June 26. Solar wind speed ranged between 427 and 528 km/sec under the influence of a fairly benign coronal stream. Solar flare activity was low. Solar flux was 167.9, the planetary A index was 13 (3-hour K indices: 1223 3433, Boulder K indices: 1222 2233). Region 9504 rotated well behind the west limb. Region 9506 decayed and was quiet, the region is rotating off the visible disk. Region 9511 decayed and was quiet. Region 9512 decayed slowly but may still be capable of producing a minor M class flare. Region 9513 decayed as well and was mostly quiet. Region 9514 developed slowly and was mostly quiet. Region 9515 decayed slowly and was quiet. Region 9516 was quiet and stable. Region 9517 decayed and was spotless by late evening. A new region has emerged fairly quickly at an unusually high latitude (nearly S50) in the southeast quadrant and should be numbered today. Flares and CMEs A total of 3 C class events were recorded on June 26. Region 9513 produced a C1.2 flare at 05:37 UTC. Region 9514 generated a C1.2 flare at 11:00 UTC. A long duration C7.1 event peaking at 13:12 UTC had its origin behind the southeast limb and was associated with a fairly large CME. The background x-ray flux is at the class B8 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be 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 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 Area Classification Comment midnight 9504 2001.06.13 1 N08W98 0120 HSX 9505 2001.06.14 N21W86 plage 9506 2001.06.14 2 N18W75 0170 CSO 9511 2001.06.20 14 N10W27 0070 DAO 9512 2001.06.21 23 S22W36 0150 EAI beta-gamma 9513 2001.06.21 22 N22E17 0180 FSO 9514 2001.06.22 8 N16E14 0080 CAO 9515 2001.06.23 12 S06E05 0070 DAO 9516 2001.06.23 1 N11E27 0120 HSX 9517 2001.06.25 4 S14W72 0030 CRO now spotless Total number of sunspots: 87 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) 2001.06 177.9 (1) 178.6 (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]