Solar Terrestrial Activity Report [Image] Last update January 19, 2001 at 05:05 UTC. [Solar and geomagnetic data - last 4 weeks (updated daily)] [Solar wind and electron fluence charts (updated daily)] [Solar cycles 21-23 (last update January 2, 2001) - Has cycle 23 peaked?] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update January 2, 2001)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update January 2, 2001)] [Historical solar and geomagnetic data charts 1954-2000 (last update January 18, 2001)] Recent development The geomagnetic field was quiet on January 18. Solar wind speed ranged between 321 and 369 km/sec. Solar flare activity was low. Solar flux was 151.5, the planetary A index was 4 (3-hour K indices: 0012 1222, Boulder K indices: 0012 2111). Region 9306 decayed further and was quiet, the region rotated off the visible disk early today. Region 9308 decayed slowly and was quiet. Region 9311 developed slowly and was quiet. Region 9312 was quiet and stable, the region appears to be spotless early on January 19. New region 9313 rotated into view at the southeast limb, the region could be capable of producing a minor M class flare. New region 9314 emerged in the northwest quadrant. Flares and CMEs A total of 2 C class events were recorded on January 18, none of which were optically correlated. The background x-ray flux is at the class B6 level. Coronal holes Two very small coronal holes in the southern hemisphere were in geoeffective positions on January 17-18. Any coronal stream originating from these holes is unlikely to influence the geomagnetic field to a significant degree. Forecast The geomagnetic field is expected to be mostly quiet on January 19 and quiet to unsettled on January 20-21. 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 region numbered sunspots at Area Classification Comment midnight 9305 2001.01.07 S06W82 plage 9306 2001.01.08 1 N13W87 0080 HSX 9308 2001.01.10 5 N16W56 0030 CSO 9310 2001.01.14 N26W04 plage 9311 2001.01.15 16 N04E11 0060 DAO 9312 2001.01.16 2 N08E36 0020 HSX 9313 2001.01.18 14 S08E72 0120 DAO beta-gamma? 9314 2001.01.18 1 N15W44 0000 AXX Total number of sunspots: 39 Monthly solar data Month Average solar International sunspot Smoothed sunspot flux number number 1999.11 191.5 133.2 111.0 (+3.2) 1999.12 169.8 84.6 111.1 (+0.1) 2000.01 158.1 90.1 112.9 (+1.8) 2000.02 174.1 112.9 116.7 (+3.8) 2000.03 208.2 138.5 119.9 (+3.2) 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) 2000.07 202.3 169.1 (120.3 predicted, +1.6) 2000.08 163.0 130.5 (120.8 predicted, +0.5) 2000.09 182.1 109.9 (119.9 predicted, -0.9) 2000.10 167.4 100.1 (118.7 predicted, -1.2) 2000.11 178.8 106.5 (116.8 predicted, -1.9) 2000.12 173.6 104.5 (114.2 predicted, -2.6) 2001.01 170.0 (1) 85.2 (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 noted in solar links. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club] [DX News] [StudyWeb]