Last major update issued on November 27, 2004 at 04:35 UTC.
[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update November 4, 2004)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update November 4, 2004)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update November 4, 2004)]
[Historical solar and geomagnetic data charts 1954-2004 (last update November 8, 2004)]
[Archived reports (last update November 20, 2004)]
The geomagnetic field was quiet to active on November 26. Solar wind speed ranged between 370 and 529 km/sec slowly decreasing most of the day.
Solar flux measured at 20h UTC on 2.8 GHz was 111.1. The planetary A
index was 13 (STAR Ap - based on the mean of three hour interval ap indices: 13.0).
Three hour interval K indices: 33342223 (planetary), 34442223 (Boulder).
The background x-ray flux is at the class B3 level.
At midnight there were 4 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 10704 decayed slowly and quietly.
November 24-26: No obviously Earth directed CMEs 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
Large and well defined recurrent trans equatorial coronal hole CH129 will rotate into a geoeffective position on November 26-28. This coronal hole has developed quickly over the last rotation.
Processed SOHO/EIT 284 image at 01:06 UTC on November 27. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to unsettled on November 27-28 and most of November 29. During the latter half of November 29 a strong high speed stream from coronal hole CH129 is expected to arrive. This will cause unsettled to major storm conditions until December 1.
|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 poor. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant station tonight: Radio Vibración (Venezuela). On other frequencies propagation was best towards the Caribbean with Puerto Rico noted on 1520 and 1600 kHz and Antigua & Barbuda on 620 kHz. Only a single North American station was observed, Greenland on 650 kHz with a fair signal.
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|
classification was HSX
at midnight, area 0040,
classification was DSO
at midnight. area 0090
classification was DAC
at midnight, area 0100
classification was CAO
at midnight, area 0090
|Total spot count:||21||20|
flux at Earth
|International sunspot number||Smoothed sunspot number|
cycle 23 sunspot max.
|2004.05||99.8||41.5||(42.8 predicted, -2.7)|
|2004.06||97.4||43.2||(40.0 predicted, -2.8)|
|2004.07||119.1||51.0||(38.2 predicted, -1.8)|
|2004.08||109.6||40.9||(36.6 predicted, -1.6)|
|2004.09||103.1||27.7||(34.7 predicted, -1.9)|
|2004.10||105.9||48.4||(32.5 predicted, -2.2)|
|2004.11||113.5 (1)||63.4 (2)||(31.0 predicted, -1.5)|
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.