Last major update issued on January 23, 2005 at 04:20 UTC.
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(last update January 2, 2005)]
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2, 2005)]
[Historical solar and
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2004)]
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(last update January 19, 2005)]
The geomagnetic field was unsettled to major storm on January 22. Solar wind speed ranged between 670 and 1002 km/sec. A high speed stream from coronal hole CH140 was dominating the solar wind by the end of the day.
Solar flux measured at 20h UTC on 2.8 GHz was 102.2. The planetary
A
index was 28 (STAR Ap - based on the mean of three hour interval ap
indices: 27.6).
Three hour interval K indices: 56333343 (planetary), 46332233 (Boulder).
The background x-ray flux is at the class B3 level.
At midnight there were 3 spotted regions on the visible solar disk. The solar flare activity level was low. A total of 5 C class events was recorded during the day. Region 10718 behind the southwest limb was the source of a C3.1 flare at 04:32 UTC.
Region 10720 rotated out of view early in the day. Another major proton flare is possible while the region is 1-2 days behind the northwest limb. Flares: C1.3 at 12:45, C1.6 at 20:53, C1.4 at 21:00 and C1.9 at 21:13 UTC.January 21-22: No obvious 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 coronal hole (CH140) in the northern hemisphere was in a geoeffective position on January 18-20. A recurrent trans equatorial coronal hole (CH141) will likely rotate to a geoeffective position on January 27-29.
Processed SOHO/EIT 284 image at 19:06 UTC on January 22. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to active on January 23-24 due to a high speed stream from coronal hole CH140. Mostly quiet conditions are likely on January 25-26.
| 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) 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.
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is very poor. Propagation along long distance north-south paths is fair. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant station tonight: Radio Vibración (Venezuela). On other frequencies quite a few stations from Puerto Rico were noted above 1350 kHz. The Florida station on 1700 kHz was weakly audible at times. Below 1000 kHz propagation was different with most of the observed stations from Uruguay, both 770 and 930 kHz had good signals and there was an interesting station on 580 kHz.
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 |
|---|---|---|---|---|---|---|---|
| 10720 | 2005.01.10 | 6 | N11W93 | 0900 | DKC | rotated out of view | |
| 10721 | 2005.01.16 | S03W63 | plage | ||||
| 10722 | 2005.01.16 | N19W77 | plage | ||||
| 10723 | 2005.01.17 | 3 | 1 | N07E07 | 0120 | CSO | classification was HSX at midnight, area 0070 |
| 10724 | 2005.01.18 | S12W59 | plage | ||||
| 10725 | 2005.01.21 | 9 | 9 | S04W49 | 0190 | DSI |
classification was DAO at midnight, area 0100 location: S04W52 |
| 10726 | 2005.01.21 | 2 | 2 | S01E14 | 0020 | CRO |
classification was BXO at midnight, area 0010 location: S02E12 |
| S495 | visible on 2005.01.13 |
S06W22 | plage | ||||
| S500 | visible on 2005.01.18 |
N10E18 | plage | ||||
| Total spot count: | 20 | 12 | |||||
| SSN: | 60 | 42 | |||||
| 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) |
| 2003.11 | 140.8 | 67.3 | 56.7 (-1.5) |
| 2003.12 | 114.9 | 46.5 | 54.8 (-1.9) |
| 2004.01 | 114.1 | 37.3 | 52.0 (-2.8) |
| 2004.02 | 107.0 | 45.8 | 49.3 (-2.7) |
| 2004.03 | 112.0 | 49.1 | 47.1 (-2.2) |
| 2004.04 | 101.2 | 39.3 | 45.5 (-1.6) |
| 2004.05 | 99.8 | 41.5 | 43.9 (-1.6) |
| 2004.06 | 97.4 | 43.2 | 41.7 (-2.2) |
| 2004.07 | 119.1 | 51.0 | (39.6 predicted, -1.9) |
| 2004.08 | 109.6 | 40.9 | (38.0 predicted, -1.6) |
| 2004.09 | 103.1 | 27.7 | (36.1 predicted, -1.9) |
| 2004.10 | 105.9 | 48.4 | (33.9 predicted, -2.2) |
| 2004.11 | 113.2 | 43.7 | (32.0 predicted, -1.9) |
| 2004.12 | 94.5 | 17.9 | (29.7 predicted, -2.3) |
| 2005.01 | 107.5 (1) | 39.5 (2) | (27.0 predicted, -2.7) |
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% less.
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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