Solar Terrestrial Activity Report [Planetary A Index, Solar Flux and SEC sunspot number] Last update December 3, 1999 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 December 2, 1999)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update December 2, 1999)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update December 2, 1999)] [Historical solar and geomagnetic data charts 1954-1999] [Experimental solar data chart January 1998-September 1999] Recent development The geomagnetic field was quiet on December 2. Solar wind speed ranged between 317 and 406 km/sec. A coronal stream was noticeable as solar wind speed increased slowly after 18h UTC, the coronal stream has dominated the solar wind early on Dec.3. Solar flare activity was low. Solar flux was 165.5, the planetary A index was 4 (3-hour Kp indices: 2001 1122, Boulder K indices: 1110 1211). Region 8778 rotated off the visible disk. Region 8780 decayed into spotless plage. Region 8781 was mostly stable and quiet, the region has an outside chance of producing an isolated minor M class flare. Region 8782 was mostly unchanged and will likely continue to produce C flares. An isolated minor M class flare is possible. Regions 8783 and 8784 were quiet and stable, region 8784 appears to be spotless early on Dec.3. Region 8785 was quiet and stable. New region 8786 emerged early in the day in the northeast quadrant near the central meridian, the region appears to be decaying already and could disappear today or tomorrow. New region 8787 emerged in the northeast quadrant. New region 8788 rotated partly into view at the northeast limb, the region could be capable of M class flaring. New region 8789 emerged in the northwest quadrant near region 8786, the region could already be decaying. Flares and CMEs 6 C flares were recorded on December 2 with the most energetic flare of the day, a C5.3 event at 10:12 UTC, being optically unaccounted. The background x-ray flux is at the class C1 level. Coronal holes A large trans equatorial coronal hole will rotate into a geoeffective position December 1-6. Forecast The geomagnetic field is expected to be unsettled to minor storm December 3-9, isolated major storm intervals are possible. Low frequency (below 2 MHz) radio wave propagation along east-west paths over high and upper middle latitudes is generally fair and is deteriorating. 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 8778 991121 5 S12W91 0180 CAO 8780 991124 S15W52 8781 991124 20 S12W29 0280 EAO 8782 991127 14 N11W68 0400 EAI 8783 991130 1 S16W72 0010 HRX 8784 991130 4 N30E05 0030 CRO 8785 991201 2 N14E58 0160 HAX 8786 991202 4 N22W07 0010 CRO 8787 991202 2 N14E46 0000 BXO 8788 991202 1 N13E78 0180 HKX 8789 991202 3 N29W10 0000 BXO Total number of sunspots: 56 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 9810 117.2 55.5 70.5 (+1.0) 9811 140.1 74.0 73.0 (+2.5) 9812 150.1 81.9 77.9 (+4.9) 9901 140.6 62.0 82.6 (+4.7) 9902 141.9 66.3 84.6 (+2.0) 9903 126.3 68.8 83.8 (-0.8) 9904 117.2 63.7 85.4 (+1.6) 9905 148.4 106.4 90.4 (+5.0) 9906 169.8 137.7 (94.4 predicted, +4.0) 9907 165.6 113.5 (99.4 predicted, +5.0) 9908 170.7 93.7 (105.3 predicted, +5.9) 9909 135.7 70.6 9910 164.8 116.4 9911 191.5 132.7 9912 165.3 (1) 8.9 (2) 1) Running average based on the daily 20:00 UTC solar flux measurement at 2800 MHz by DRAO. 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]