Solar Terrestrial Activity Report [Image] Last update June 22, 2000 at 05:15 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 2, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update June 2, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update June 2, 2000)] [Historical solar and geomagnetic data charts 1954-2000 (last update April 12, 2000)] Recent development The geomagnetic field was quiet to unsettled on June 21. Solar wind speed ranged between 337 and 393 km/sec. Solar flare activity was moderate. Solar flux was 188.0, the planetary A index was 8 (3-hour K indices: 2112 2333, Boulder K indices: 1111 1213). Region 9036 was quiet and rotated over the west limb. Region 9040 was mostly quiet and stable. Region 9042 decayed slowly and will likely continue to produce fairly frequent C flares and occasional minor M flares. Region 9046 decayed slowly, however, the region is gradually becoming more complex and has a fairly good chance of producing an M flare. Region 9048 decayed slowly and was quiet, the region is rotating off the visible disk. Regions 9049, 9050 and 9051 were quiet and stable. Region 9052 lost some spots and was quiet. Occasional C flares are possible. Region 9053 was quiet and stable, as was region 9054. New region 9055 rotated into view at the northeast limb. New region 9056 rotated into view at the southeast limb. Flares and CMEs A total of 7 C flares and 1 M flare were observed on June 21. Region 9042 produced a C3.9/1N flare at 08:00 UTC. This was accompanied by a weak type II sweep. The region was the source of an M1.3 flare at 09:29, a C9.7/1N flare at 14:25 and a C2.1 flare at 22:21 UTC. Region 9040 generated a C3.2 flare at 19:38 UTC. Region 9051 was at the center of a long duration C4.7 event at 09:02 UTC. A filament erupted and a weak, apparently full halo CME was observed in LASCO C2 and C3. This CME could impact Earth on June 24. The background x-ray flux is at the class C1 level. Coronal holes A well defined coronal hole in the southern hemisphere will likely rotate into a geoeffective position on June 23-24. Forecast The geomagnetic field is expected to be quiet to unsettled on June 22. Long distance medium wave (AM) band propagation along east-west paths over high and upper middle latitudes is fair. 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 9036 20000608 1 S19W91 0060 HSX 9040 20000611 3 N19W58 0060 CRO 9042 20000612 36 N23W38 0240 FAO beta-gamma 9045 20000614 S17W72 plage 9046 20000614 29 N21W07 0390 DKO beta-gamma 9047 20000615 S27W43 plage 9048 20000616 1 N08W85 0030 HSX 9049 20000616 1 S36E00 0000 AXX 9050 20000617 16 S08W48 0090 DSO 9051 20000617 1 N18E10 0000 AXX 9052 20000618 4 S26W52 0120 DSO 9053 20000619 1 N04E20 0000 AXX 9054 20000620 1 N11E47 0030 HSX 9055 20000621 1 N19E70 0080 HSX 9056 20000621 1 S15E68 0130 HSX Total number of sunspots: 96 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.05 148.4 106.3 90.5 (+5.0) 1999.06 169.8 137.7 93.1 (+2.6) 1999.07 165.6 113.5 94.5 (+1.4) 1999.08 170.7 93.7 97.4 (+2.9) 1999.09 135.7 71.5 102.3 (+4.8) 1999.10 164.8 116.7 107.7 (+5.4) 1999.11 191.5 133.2 110.9 (+3.2) 1999.12 169.8 84.6 (111.2 predicted, +0.3) 2000.01 158.1 90.2 (112.4 predicted, +1.2) 2000.02 174.1 112.3 (115.8 predicted, +3.4) 2000.03 208.2 138.2 (119.6 predicted, +3.8) 2000.04 184.2 125.3 (121.7 predicted, +2.1) 2000.05 184.9 120.8 2000.06 182.9 (1) 135.0 (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 in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]