Last major update issued on February 9, 2010 at 05:55 UTC.
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The geomagnetic field was quiet on February 8. Solar wind speed ranged between 286 and 363 km/s.
Solar flux measured at 20h UTC on 2.8 GHz was 93.7. The planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 3.1). Three hour interval K indices: 22100001 (planetary), 23100002 (Boulder).
The background x-ray flux is at the class B1 level.
At midnight there were 3 spotted regions on the visible solar disk.
Region 11045 was strongly affected by the intense flare activity. A
large reduction in penumbral area was observed and the region no longer has any
magnetic delta structures. Further M class flares are possible, however, in
general flare activity is expected to decrease strongly.
Region 11046 was quiet and stable.
New region 11047 rotated into view at the southeast limb.
February 6: A CME was observed off of the east limb after an M2 flare in region 11045.
February 7: A full halo CME was observed following an M6 flare in region 11045.
February 8: No obvious Earth directed CMEs were observed in LASCO images.
Coronal hole history (since late October 2002)
Compare today's report to the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago
A recurrent coronal hole (CH390) in the northern hemisphere was in an Earth facing position on February 6-7. A coronal hole (CH391) in the southern hemisphere may have closed before reaching an Earth facing position.
Processed SOHO/EIT 195 image at 23:48 UTC on February 8. The darkest areas on the solar disk are likely coronal holes.
Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over high and upper middle latitudes is fair. Propagation on long distance northeast-southwest paths is poor.
The geomagnetic field is expected to be quiet initially on February 9. Later in the day or early on February 10 a CME associated with an M6 event in region 11045 on February wil likely impact the fiedl and cause unsettled to minor storm conditions, possibly with major storm intervals. A high speed stream from CH390 could cause unsettled to active conditions on February 10.
|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.
Compare to the previous day's image.
Data for all numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC. 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 SWPC or where SWPC has observed no spots. SWPC active region numbers in the table below and in the active region map above are the historic SWPC/USAF numbers.
|Active region||Date numbered||SWPC
|Location at midnight||Area||Classification||Comment|
area was 0250 at midnight, classification FAI
|11046||2010.02.07||4||2||N24E52||0030||BXO||classification was DSO at midnight|
|11047||2010.02.08||2||1||S15E70||0010||AXX||classification was HSX at midnight, area 0020|
|Total spot count:||41||35|
|Month||Average measured solar flux||International sunspot number (SIDC)||Smoothed sunspot number||Average Ap
cycle 23 sunspot max.
|2009.08||67.3||0.0||(4.5 predicted, +0.9)||5.70|
|2009.09||70.5||4.2||(5.5 predicted, +1.0)||3.88|
|2009.10||72.6||4.6||(6.6 predicted, +1.1)||3.66|
|2009.11||73.6||4.2||(7.8 predicted, +1.2)||2.45|
|2009.12||76.7||10.6||(9.2 predicted, +1.4)||1.41 / 1.92|
|2010.01||81.1||13.1||(11.0 predicted, +1.8)||2.93|
|2010.02||81.0 (1)||7.9 (2)||(13.0 predicted, +2.0)||(4.92)|
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/SWPC) sunspot number. The official international sunspot number is typically 30-50% lower.
3) Running average based on the daily SWPC ap indices. Values in red are based on official NGDC records.
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.