Solar Terrestrial Activity Report [Image] Last update March 6, 2001 at 04:30 UT. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update March 1, 2001) - Cycle 23 sunspot maximum was in April 2000] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update March 1, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update March 1, 2001)] [Historical solar and geomagnetic data charts 1954-2000 (last update January 18, 2001)] Recent development The geomagnetic field was quiet to minor storm on March 5. Solar wind speed ranged between 427 and 588 km/sec. A coronal stream arrived early in the day, this stream turned out to be fairly benign and the geomagnetic field was mostly quiet during the latter half of the day. Solar flare activity was low. Solar flux was 155.8, the planetary A index was 18 (3-hour K indices: 5444 2221, Boulder K indices: 5434 3321). Region 9364 produced a few flares and rotated out of view by the evening. Region 9365 was quiet and stable. Region 9366 decayed slowly and was quiet. Region 9367 was quiet and stable. Region 9368 developed slowly and was quiet, C and minor M class flares are possible. Region 9369 was mostly quiet and stable, the region will rotate over the west limb today and early tomorrow. Region 9370 was quiet and stable. Region 9371 developed slowly and could produce C class flares. Flares and CMEs A total of 8 C class events were observed on March 5. Region 9364 produced a C1.1 flare at 08:55 UT, otherwise the flares were optically uncorrelated. A full halo CME was observed in LASCO C3 images starting at 04:42 UT over the northwest limb. Unfortunately the LASCO-EIT movie is currently useless and it is difficult to be certain where the source of the CME was. With no flares having occurred within a few hours before the first CME observation it is likely that the source was on the backside of the sun. The background x-ray flux is at the class B5 level. Coronal holes No obvious coronal holes are currently approaching geoeffective positions. Forecast The geomagnetic field is expected to be quiet to unsettled on March 6-7. 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 9364 2001.02.28 3 S10W82 0070 DSO 9365 2001.02.28 2 S10W34 0020 HSX 9366 2001.03.02 16 S25E00 0070 EAO 9367 2001.03.02 1 N10E09 0010 HSX 9368 2001.03.02 22 N26E08 0220 EAO beta-gamma? 9369 2001.03.03 5 N17W76 0120 DAO 9370 2001.03.03 5 N09E28 0010 BXO 9371 2001.03.04 9 N21W51 0060 DAO beta-gamma? Total number of sunspots: 63 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.12 169.8 84.6 111.1 (+0.1) 2000.01 158.1 90.1 112.9 (+1.8) 2000.02 174.1 112.9 116.8 (+3.9) 2000.03 208.2 138.5 119.9 (+3.1) 120.8 (+0.9) 2000.04 184.2 125.5 cycle 23 peak candidate 2000.05 184.9 121.6 119.0 (-1.8) 2000.06 179.8 124.9 118.7 (-0.3) 2000.07 202.3 170.1 119.8 (+1.1) 2000.08 163.0 130.5 118.6 (-1.2) 2000.09 182.1 109.7 (115.4 predicted, -3.2) 2000.10 167.4 100.1 (113.0 predicted, -2.4) 2000.11 178.8 106.5 (111.0 predicted, -2.0) 2000.12 173.6 104.5 (108.5 predicted, -2.5) 2001.01 166.6 95.7 (104.7 predicted, -3.8) 2001.02 146.6 80.1 (100.3 predicted, -4.4) 2001.03 139.5 (1) 18.5 (2) (96.8 predicted, -3.5) 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. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]