Solar Terrestrial Activity Report [Image] Last update June 6, 2001 at 04:05 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 5. Solar wind speed ranged between 368 and 448 km/sec. Solar flare activity was moderate. Solar flux was 153.4, the planetary A index was 9 (3-hour K indices: 3312 2323, Boulder K indices: 3311 3313). Region 9475 was mostly unchanged and quiet. In recent images the region appears to be decaying. Region 9484 developed slowly and has minor M class flare potential. Region 9485 decayed slowly and was spotless by the end of the day. Region 9486 developed slowly. This reversed polarity region could produce C and minor M class flares. Region 9487 was quiet and stable and may be capable of producing occasional minor M class flares. Region 9488 appears to be losing some of its complexity as the magnetic delta (near the northern edge of the large penumbra) has become less evident. Further minor M class flares are possible. New region 9489 emerged in the northeast quadrant. New region 9490 in the southeast quadrant was finally numbered. New region 9491 rotated into view at the northeast limb. Flares and CMEs A total of 3 C and 1 M class events were recorded on June 5. Region 9488 produced an M2.5/2N flare at 04:51 UTC. Region 9484 was the source of a C9.4 flare at 14:21 UTC. Lots of CME activity was observed in LASCO images, particularly from a source just behind the northwest limb. The background x-ray flux is at the class B5 level. Coronal holes A coronal hole in the northern hemisphere will rotate into a geoeffective position on June 4-6. Forecast The geomagnetic field is expected to be quiet to unsettled on June 6 and quiet to minor storm on June 7-8. 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 9474 2001.05.26 N22W77 plage 9475 2001.05.26 13 N21W56 0160 DAO 9480 2001.05.28 S13W55 plage 9482 2001.05.30 S16W30 plage 9484 2001.06.01 23 S05W20 0240 EAO beta-gamma 9485 2001.06.01 1 S23E20 0010 AXX now spotless 9486 2001.06.02 13 N28W48 0200 DAI 9487 2001.06.02 7 N19E35 0250 CKO 9488 2001.06.03 8 S20E33 0250 DAO beta-gamma 9489 2001.06.05 3 N17E52 0040 DSO 9490 2001.06.05 1 S13E49 0010 AXX 9491 2001.06.05 1 N22E75 0090 HSX Total number of sunspots: 70 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 (110.5 predicted, -2.3) 2001.01 166.6 95.6 (106.8 predicted, -3.7) 2001.02 146.6 80.6 (102.4 predicted, -4.4) 2001.03 177.7 113.5 (98.8 predicted, -3.6) 2001.04 177.7 108.2 (97.6 predicted, -1.2) 2001.05 147.1 97.3 (96.9 predicted, -0.7) 2001.06 143.9 (1) 23.0 (2) (94.2 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]