Solar Terrestrial Activity Report [Image] Last update January 6, 2003 at 03:25 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 1, 2003)] [Solar cycles 1-20] [Graphical comparison of cycles 21, 22 and 23 (last update January 1, 2003)] [Graphical comparison of cycles 10, 13, 17, 20 and 23 (last update January 1, 2003)] [Historical solar and geomagnetic data charts 1954-2002 (last update October 13, 2002)] [Archived reports (last update January 6, 2003)] Recent activity The geomagnetic field was quiet to unsettled on January 5. Solar wind speed ranged between 377 and 480 km/sec. Solar flux measured at 20h UTC on 2.8 GHz was 148.1. The planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 9.0). Three hour interval K indices: 22223332 (planetary), 12212222 (Boulder). The background x-ray flux is at the class B4 level. At midnight there were 7 spotted regions on the visible disk, 3 of which have not yet been numbered. Solar flare activity was low. A total of 3 C class events were recorded during the day. Region 10242 developed further, particularly in the trailing spot section. A minor M class flare is possible. Flare: C1.0 at 07:58 UTC. Region 10243 added a few trailing spots while decay was observed in the leading spots. Flare: C5.8 at 06:17 UTC. Region 10244 did not change much and was mostly quiet. Flare: C1.3 at 11:54 UTC. Region 10245 decayed slowly and quietly. Spotted regions not yet numbered by SEC/NOAA: [S66] A new region emerged to the northeast of region 10239 on January 4. The region was mostly unchanged un January 5. Location at midnight: S05W50. Unfortunately and confusingly SEC/NOAA decided to reuse region number 10240. [S69] A new region emerged in the northeast quadrant near the central meridian late on January 5. Location at midnight: N13E01. [S70] A new region emerged quickly in the northeast quadrant late on January 5. Location at midnight: N09E27. Coronal mass ejections (CMEs) January 3-5: No obviously geoeffective CMEs observed. Coronal holes Coronal hole history (since late October 2002) Compare today's report with the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago A recurrent trans equatorial extension of the northern polar coronal hole will rotate into a geoeffective position on January 6-7. [Image] Processed SOHO EIT 284 image at 01:06 UTC on January 6. Any black areas on the solar disk are likely coronal holes. Forecast The geomagnetic field is expected to be quiet to unsettled on January 6-8 becoming quiet to active on January 9-10 due to a coronal stream. 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) [Image] Composite image based on a SOHO/MDI continuum image and overlaid by a coronal hole image. Region numbering has been included. Compare to the previous day's image. Data for all numbered solar regions according to the Solar Region Summary provided by SEC/NOAA. Comments are my own, as is the STAR spot count (spots observed at or inside a few hours before midnight) and data for regions not numbered by SEC or where SEC has observed no spots. Solar Date SEC STAR Location region numbered spot spot at AreaClassification Comment countcount midnight 10234 2002.12.24 N19W86 plage 10238 2002.12.28 N09W89 plage S09W56 actually spotless, 10239 2002.12.29 7 (SEC: 0030 CSO location corrected S07W54) see region S66 S08W43 actually spotless 10240 2002.12.30 2 (SEC: 0010 HRX location corrected S08W53) see region S66 below 10241 2003.01.02 S24W79 plage area approx. 0300 10242 2003.01.02 28 30 S08E20 0190 DAI at midnight, classification EAI 10243 2003.01.03 13 15 S19W60 0200 DAO 10244 2003.01.03 15 13 S23E27 0150 DAO 10245 2003.01.03 3 3 N11E46 0080 HAX S66 emerged on 8 S05W50 0030 DSO 2003.01.04 S67 emerged on S15E42 plage 2003.01.04 S68 emerged on N02E32 plage 2003.01.04 S69 emerged on 1 N13E01 0020 HRX 2003.01.05 S70 emerged on 4 N09E27 0020 DSO 2003.01.05 Total spot count: 68 74 SSN: 128 144 Monthly solar cycle data Average Month solar International sunspot Smoothed sunspot flux at number number Earth 2000.04 184.2 125.5 120.8 cycle 23 sunspot max. 2000.07 202.3 170.1 119.8 2001.12 235.1 132.2 114.6 (-0.9) 2002.01 226.6 114.1 113.5 (-1.1) 2002.02 205.0 107.4 114.6 (+1.2) 2002.03 179.5 98.4 113.3 (-1.3) 2002.04 189.8 120.7 110.5 (-2.9) 2002.05 178.4 120.8 108.8 (-1.7) 2002.06 148.7 88.3 106.2 (-2.6) 2002.07 173.5 99.6 (102.1 predicted, -4.1) 2002.08 183.6 116.4 (98.5 predicted, -3.6) 2002.09 175.8 109.6 (95.5 predicted, -3.0) 2002.10 167.0 97.5 (92.0 predicted, -3.5) 2002.11 168.7 95.0 (86.7 predicted, -5.3) 2002.12 157.2 81.6 (82.4 predicted, -4.3) 2003.01 132.4 (1) 15.3 (2) (79.4 predicted, -3.0) 1) Running average based on the daily 20:00 UT observed 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 25-45% 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. All time references are to the UTC day. Comments and suggestions are always welcome. ------------------------------------------------------------------------ [DX-Listeners' Club]