Last major update issued on January 20, 2006 at 04:55 UTC.
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The geomagnetic field was quiet to unsettled on January 19. Solar wind speed ranged between 422 and 512 (all day average 454) km/sec.
Solar flux measured at 20h UTC on 2.8 GHz was 88.6. The planetary A
index was 7 (STAR Ap - based on the mean of three hour interval ap
indices: 7.0).
Three hour interval K indices: 21223212 (planetary), 11223212 (Boulder).
The background x-ray flux is at the class A4 level.
At midnight there were 2 spotted regions on the visible solar disk. The solar flare activity level was very low. No C class events were recorded during the day.
Region 10847 decayed further and had only a tiny spot at midnight.
Region 10848 matured with penumbral area increasing and the opposite polarity areas increasing their separation.
January 17-19: No obviously fully or partly Earth directed CMEs were observed.
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 coronal hole (CH206) will likely rotate to an Earth facing position late on January 21-22. CH206 appears to have decayed quite a bit over the last solar rotation. A small coronal hole currently in the southwest quadrant was in an Earth facing position on January 17-18.
Processed SOHO/EIT 284 image at 01:06 UTC on January 20. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to unsettled on January 20-22 and become unsettled to active on January 23-24 due to effects from CH206.
Coronal holes (1) | Coronal mass ejections (2) | M and X class flares (3) |
1) Effects from a coronal hole could reach Earth
within the next 5 days. When the high speed stream has arrived the color changes to green.
2) Effects from a CME are likely to be observed at 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.
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is fair to good. Propagation on long distance northeast-southwest paths is very poor. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant station tonight: WLAM Lewiston ME. On other frequencies lots of stations from the eastern parts of North America were audible. Stations from the New York area had the best signals.
Compare to the previous day's image.
Data for all numbered solar regions according to the Solar Region Summary provided by NOAA/SEC. 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. SEC active region numbers in the table below and in the active region map above are the historic SEC/USAF numbers.
Active region | Date numbered | SEC spot count |
STAR spot count |
Location at midnight | Area | Classification | Comment |
---|---|---|---|---|---|---|---|
10846 | 2006.01.15 | 1 | N04W88 | 0020 | AXX | rotated out of view | |
10847 | 2006.01.15 | 2 | 1 | S08W62 | 0030 | CSO | classification was AXX at midnight, area 0000 |
10848 | 2006.01.18 | 15 | 12 | S19E24 | 0140 | DAO | |
Total spot count: | 18 | 13 | |||||
SSN: | 48 | 33 |
Month | Average solar flux at Earth |
International sunspot number | Smoothed sunspot number |
---|---|---|---|
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) |
2004.11 | 113.2 | 43.5 | 35.3 (-0.6) |
2004.12 | 94.5 | 17.9 | 35.2 (-0.1) |
2005.01 | 102.2 | 31.3 | 34.6 (-0.6) |
2005.02 | 97.2 | 29.2 | 33.9 (-0.7) |
2005.03 | 89.9 | 24.5 | 33.5 (-0.4) |
2005.04 | 86.0 | 24.4 | 31.6 (-1.9) |
2005.05 | 99.3 | 42.6 | 28.9 (-2.7) |
2005.06 | 93.7 | 39.6 | 28.8 (-0.1) |
2005.07 | 96.4 | 39.9 | (29.1 predicted, +0.3) |
2005.08 | 90.5 | 36.4 | (27.4 predicted, -1.7) |
2005.09 | 91.1 | 22.1 | (25.4 predicted, -2.0) |
2005.10 | 77.0 | 8.5 | (23.4 predicted, -2.0) |
2005.11 | 86.3 | 18.0 | (21.0 predicted, -2.4) |
2005.12 | 90.7 | 41.2 | (18.2 predicted, -2.8) |
2006.01 | 81.5 (1) | 15.0 (2) | (15.2 predicted, -3.0) |
1) Running average based on the
daily 20:00 UTC observed solar flux
value at 2800 MHz.
2) Unofficial, accumulated value based on the Boulder (NOAA/SEC)
sunspot number. The official international sunspot number is typically
30-50% lower.
This report has been prepared by Jan Alvestad. It is based partly on my own observations and analysis, and partly on data from some of these solar data sources. All time references are to the UTC day. Comments and suggestions are always welcome.
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