Solar Terrestrial Activity Report [Image] Last update March 6, 2000 at 04:20 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update March 2, 2000)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update March 2, 2000)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update March 2, 2000)] [Historical solar and geomagnetic data charts 1954-1999] Recent development The geomagnetic field was quiet to unsettled on March 5. Solar wind speed ranged between 337 and 381 km/sec. A minor disturbance arrived shortly before 02h UTC on March 6. Solar flare activity was low. Solar flux was 220.3, the planetary A index was 7 (3-hour K indices: 2212 2223, Boulder K indices: 0313 1333). Region 8882 rotated off the visible disk. Region 8889 was quiet and stable. Region 8891 developed slowly and could produce a major flare. Region 8896 was quiet and stable, as was region 8897. Region 8898 developed fairly quickly and produced lots of C flares. The region has at least minor M class flaring potential. Region 8899 was quiet and stable. Region 8900 continued to develop quickly and has at least minor M class flaring potential. New region 8901 rotated into view at the southeast limb. Flares and CMEs 14 C flares were recorded on March 5. Region 8891 produced a C5.1 flare at 09:02 UTC. All other optically assigned flares had their origin in region 8898. This very active region generated a C3.9 flare at 05:17, a C4.2 flare at 06:51, a C5.1 flare at 09:02, a C6.8 flare at 09:43, a C9.6 flare at 15:30, a C5.0 flare at 16:27 UTC and several minor C flares. A strong type II sweep was observed at 22:20 UTC, its source was not obvious in LASCO-EIT images. A fairly large eruption of the northern polar crown filament was observed in the northwest quadrant starting at 16:00 UTC. A filament eruption was observed over the central meridian near the solar equator starting at 07:48 UTC in LASCO-EIT. LASCO C2 images may indicate a partial halo CME as the result of this eruption, however, nearly continuous CMEs from the back side of the sun and the solar limbs makes it very difficult to state with an acceptable degree of certainty that there was a halo CME. March 4: A filament eruption started at 16:24 in LASCO EIT images to the southeast of regions 8899 and 8900. There is a small chance the associated CME could be geoeffective, any impact would most likely occur on March 8. The background x-ray flux is at the class C1 level. Coronal holes No obvious coronal holes are approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to active on March 6-7. Unsettled to active is possible on March 8-9 due to CME activity. 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 8882 20000221 2 S16W96 0300 DKC 8887 20000224 S11W82 plage 8888 20000224 N37W66 plage 8889 20000224 3 N20W61 0180 EAO 8890 20000224 S11W66 plage 8891 20000225 31 S16W43 0730 DKC beta-gamma 8892 20000226 N06W38 plage 8896 20000229 5 N19W03 0030 CSO 8897 20000301 3 S36W64 0110 DSO 8898 20000302 14 S13E34 0140 DAO 8899 20000303 9 S10E06 0020 DAO 8900 20000304 22 S16E02 0230 DAI 8901 20000305 2 S13E71 0010 AXX Total number of sunspots: 91 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.02 141.9 66.1 84.6 (+2.0) 1999.03 126.3 69.1 83.8 (-0.8) 1999.04 117.2 63.9 85.4 (+1.6) 1999.05 148.4 106.3 90.4 (+5.0) 1999.06 169.8 137.7 93.0 (+2.6) 1999.07 165.6 113.5 94.4 (+1.4) 1999.08 170.7 93.7 97.5 (+3.1) 1999.09 135.7 70.9 (102.6 predicted, +5.1) 1999.10 164.8 116.4 (107.7 predicted, +5.1) 1999.11 191.5 132.7 (110.2 predicted, +2.5) 1999.12 169.8 86.4 2000.01 158.1 90.2 2000.02 174.1 112.3 2000.03 214.1 (1) 31.1 (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]