Solar Terrestrial Activity Report

Last major update issued on November 10, 2004 at 04:15 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 8, 2004)]

Recent activity

The geomagnetic field was at minor to very severe storm levels on November 9. Solar wind speed ranged between 505 and 961 km/sec. Two solar wind shocks were observed during the day at SOHO, the first was at 09:05 when solar wind speed increased quickly from 580 to 700 km/sec. The second and most significant one was at 18:24 UTC with an abrupt increase in solar wind speed from 620 to 800 km/sec. These solar wind shocks were likely related to CMEs observed on November 7.

Solar flux measured at 22h UTC on 2.8 GHz was 126.6 (the measurements at 18 and 20h UTC were flare enhanced). The planetary A index was 120 (STAR Ap - based on the mean of three hour interval ap indices: 119.6).
Three hour interval K indices: 66576787 (planetary), 66566677 (Boulder).

The background x-ray flux is at the class C1 level.

At midnight there were 4 spotted regions on the visible solar disk. The solar flare activity level was high. A total of 7 C and 1 M class events was recorded during the day.

Region 10696 decayed fairly quickly, particularly in the intermediate spot section. The region still has a very complex magnetic layout and could produce further M and X class flares. Flares: C2.3 at 01:43, C2.1 at 16:19 and major M8.9/2N at 17:23 UTC. The major flare was associated with strong type II and IV radio sweeps and a very fast CME. This region was the origin of a major X2.5 flare at 02:13 UTC on November 10. This event was a small proton flare as well and has caused an increase in proton levels near Earth.
Region 10698 developed moderately quickly and could soon produce M class flares, even from behind the southwest limb. Flares: C1.8 at 06:30, C1.8 at 07:45, C1.2 at 09:25, C1.2 at 13:23 and C1.0 at 13:50 UTC.
New region 10699 emerged near the southeast limb.

Spotted regions not numbered by NOAA/SEC:
[S472] This region emerged in the southwest quadrant on November 9. Location at midnight: S12W28

Coronal mass ejections (CMEs)

November 10: While no LASCO images of the event are available as I write this, another very fast CME was likely associated with the major X2.8 flare in region 10696 early in the day. This CME could reach Earth on November 11.
November 9
: A very fast full halo CME was observed after the M8 major flare in region 10696 during the afternoon. This CME could reach Earth late on November 10 or early on November 11.
November 8
: A full halo CME was observed early in the day after a long duration event in the eastern part of region 10696. This CME will probably reach Earth late on November 10 or on November 11.

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

Trans equatorial coronal hole CH125 was in a geoeffective position on November 8, however, most of this coronal hole closed after the long duration event in region 10696 early in the day. Recurrent coronal hole CH126 in the southern hemisphere is poorly defined and will be in a geoeffective position on November 10-11.

Processed SOHO/EIT 284 image at 19:06 UTC on November 9. The darkest areas on the solar disk are likely coronal holes.


The geomagnetic field is expected to be active to very severe storm on November 10-12 due to the arrival of 3 CMEs.

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.


Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is useless. Propagation along long distance north-south paths is poor to very poor. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant stations tonight: none, weak audio from a Spanish speaking station was noted, probably from Radio Cristal del Uruguay. On other frequencies (610, 740, 760, 840, 930 kHz) some weak signals from Brazil could be heard while Argentinean stations were observed on 950 and 1030 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
Location at midnight Area Classification Comment
10693 2004.10.27 2   S18W93 0070 HAX rotated out of view
10695 2004.10.30     S16W66     plage
10696 2004.11.01 37 29 N08W50 0730 EKC beta-gamma-delta
classification was EKI
at midnight, area 0450
10698 2004.11.06 9 14 S09W84 0160 DAO  
10699 2004.11.09 2 2 S16E66 0020 HRX classification was HSX
at midnight
S470 emerged on
    N05W15     plage
S471 emerged on
    N04E23     plage
S472 emerged on
  1 S12W28 0000 AXX  
Total spot count: 50 46
SSN: 90 86

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)
2003.08 122.1 72.7 60.0 (-1.7)
2003.09 112.2 48.7 59.5 (-0.5)
2003.10 151.7 65.5 58.2 (-1.3)
2003.11 140.8 67.3 56.7 (-1.5)
2003.12 114.9 46.5 54.8 (-1.9)
2004.01 114.1 37.3 52.0 (-2.8)
2004.02 107.0 45.8 49.3 (-2.7)
2004.03 112.0 49.1 47.1 (-2.2)
2004.04 101.2 39.3 45.5 (-1.6)
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)
2004.11 132.3 (1) 32.6 (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.

[DX-Listeners' Club]