Solar Terrestrial Activity Report

Last major update issued on November 22, 2005 at 05:40 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update November 9, 2005)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update November 9, 2005)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update November 9, 2005)]
[Historical solar and geomagnetic data charts 1954-2004 (last update February 1, 2005)]
[Archived reports (last update November 2, 2005)]

Recent activity

The geomagnetic field was inactive to quiet on November 21. Solar wind speed ranged between 330 and 363 (all day average 349) km/sec.

Solar flux measured at 20h UTC on 2.8 GHz was 94.7. The planetary A index was 3 (STAR Ap - based on the mean of three hour interval ap indices: 3.3)
Three hour interval K indices: 22001101 (planetary), 22112110 (Boulder).

The background x-ray flux is at the class B1 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 was recorded during the day.

Region 10822 decayed in the trailing and intermediate spot sections while new spots emerged immediately to the southeast of the leading penumbra. C flares are possible.
Region 10824 was quiet but does have C class flare potential.

Coronal mass ejections (CMEs)

November 19-21: No obvious fully or partly Earth directed CMEs were observed. A complex full halo CME was observed on Nov.21, its origin was most likely backsided.

Coronal holes

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

The northernmost extension of a southern hemisphere coronal hole (CH199) was in a potentially geoeffective position on November 20.

Processed SOHO/EIT 284 image at 01:06 UTC on November 22. The darkest areas on the solar disk are likely coronal holes.

Forecast

The geomagnetic field is expected to be quiet on November 22 and quiet to active on November 23 due to coronal hole effects.

Coronal holes (1) Coronal mass ejections (2) M and X class flares (3)
Coronal hole indicator CME indicator M and X class flare indicator

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.

Propagation

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 poor. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant station tonight: WWNN Pompano Beach FL. Again propagation was best to the southern parts of the USA (stations like 870 WWL, 850 WFTL, 1140 WQBA, 1700 KVNS could be heard well) and to Cuba.

Active solar regions (Recent map)

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
10822 2005.11.12 9 12 S08W37 0480 EKO  
10823 2005.11.19 2   S15W63 0030 CSO spotless
10824 2005.11.20 4 5 S12E57 0080 CAI classification was DAO at midnight
S606 2005.11.19     S10E09     plage
Total spot count: 15 17  
SSN: 45 37  

Monthly solar cycle data

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)
2004.09 103.1 27.7 37.5 (-1.7)
2004.10 105.9 48.0 35.9 (-1.6)
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 predicted, -2.7)
2005.06 93.7 39.6 (27.3 predicted, -1.6)
2005.07 96.4 39.9 (26.1 predicted, -1.2)
2005.08 90.5 36.4 (24.3 predicted, -1.8)
2005.09 91.1 22.1 (22.2 predicted, -2.1)
2005.10 77.0 8.5 (20.2 predicted, -2.0)
2005.11 86.5 (1) 21.9 (2) (17.8 predicted, -2.4)

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.


[DX-Listeners' Club]