Solar Terrestrial Activity Report

Last major update issued on November 14, 2005 at 05:10 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 quiet to active on November 13. Solar wind speed ranged between 338 and 445 (all day average 387) km/sec under the influence of a low speed stream from CH196.

Solar flux measured at 20h UTC on 2.8 GHz was 87.8. The planetary A index was 14 (STAR Ap - based on the mean of three hour interval ap indices: 14.0)
Three hour interval K indices: 34333323 (planetary), 34334223 (Boulder).

The background x-ray flux is at the class B4 level.

At midnight there was 1 spotted region on the visible solar disk. The solar flare activity level was moderate. A total of 9 C and 1 M class events were recorded during the day.

Region 10822 is a very active region with a complex layout of the magnetic fields. Negative polarity areas are at the western and eastern extremes and with with some smaller areas scattered throughout the central and trailing spot sections. Positive polarity structures cover a larger area from the eastern part of the leader spots and to include most of the trailing spot area. There is at least one magnetic delta structure and major flare activity is possible. Flares: C9.5 at 00:36, C1.8 at 03:40, C1.9 at 04:06, C5.8 at 04:45, C6.7 at 05:25, C2.7 at 06:03, C3.0 at 07:17, C2.7 at 12:49, M2.5 at 14:51 and C2.8 at 21:58 UTC.

Coronal mass ejections (CMEs)

November 10-12: No obvious fully or partly Earth directed CMEs were observed.

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

A coronal hole (CH197) in the southern hemisphere was likely in an Earth facing (potentially geoeffective) position on November 12-13.

Processed SOHO/EIT 284 image at 19:06 UTC on November 13. The darkest areas on the solar disk are likely coronal holes.

Forecast

The geomagnetic field is expected to be quiet to active on November 14-17 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 poor. Propagation on long distance northeast-southwest paths is poor. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant station tonight: Radio Vibración (Venezuela). Propagation was best to Venezuela and Colombia with good signals noted on several frequencies below 1200 kHz.

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
10821 2005.11.08     S14W84     plage
10822 2005.11.12 6 20 S06E66 0120 CAO beta-gamma-delta
classification was EKI at midnight, area 0520
S603 2005.11.06     N05W75     plage
Total spot count: 6 20  
SSN: 16 30  

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 79.5 (1) 9.2 (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]