Last major update issued on November 23, 2006 at 04:25 UTC.
geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update November 12, 2006)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update November 12, 2006)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update November 12, 2006)]
[Historical solar and geomagnetic data charts 1954-2005 (last update March 3, 2006)]
[Archived reports (last update November 12, 2006)]
The geomagnetic field was quiet to unsettled on November 22. Solar wind speed ranged between 289 and 359 km/s (all day average 333 km/s - decreasing 21 km/s from the previous day). The first parts of a disturbance associated with CH248 arrived after 17h UTC.
Solar flux measured at 20h UTC on 2.8 GHz was 76.5. The planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 4.4). Three hour interval K indices: 00001133 (planetary), 00001232 (Boulder).
The background x-ray flux is at the class A1 level.
At midnight the visible solar disk was spotless. The solar flare activity level was very low. No C class events were recorded during the day.
November 20-22: No obvious partly or fully Earth directed CMEs were detected in LASCO imagery.
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, CH248, in the southern hemisphere was in an Earth facing position on November 19-23. Only the northernmost extensions, including a trans equatorial extension in the easternmost part of the coronal hole, are within potentially geoeffective positions.
Processed SOHO/EIT 284 image at 01:06 UTC on November 23. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to unsettled on November 23-26 with occasional active intervals due to effects from CH248.
|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 good. Propagation on long distance northeast-southwest paths is poor.
Monitoring remarks from a location near N58E06: At 04:30 UTC many stations from North America were audible, some with good to excellent signals. One example is 1000 kHz were KOMO and WMVP alternated at being the dominant signal, both were stronger than any of the New York 50 kW stations. Some stations from the northeastern parts of South America and from Cuba had fair to good signals as well.
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
|Location at midnight||Area||Classification||Comment|
|Total spot count:||0||0|
flux at Earth
|International sunspot number||Smoothed sunspot number|
cycle 23 sunspot max.
|2006.05||80.9||22.2||(16.8 predicted, -0.3)|
|2006.06||76.5||13.9||(15.1 predicted, -1.7)|
|2006.07||75.7||12.2||(13.2 predicted, -1.9)|
|2006.08||79.0||12.9||(12.7 predicted, -0.5)|
|2006.09||77.8||14.5||(12.6 predicted, -0.1)|
|2006.10||74.3||10.4||(11.5 predicted, -1.1)|
|2006.11||88.2 (1)||25.5 (2)||(10.1 predicted, -1.4)|
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.