Solar Terrestrial Activity Report

Last major update issued on November 6, 2003 at 03:55 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, 2003)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update November 4, 2003)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update November 4, 2003)]
[Historical solar and geomagnetic data charts 1954-2003 (last update October 15, 2003)]
[Archived reports (last update November 5, 2003)]

Recent activity

The geomagnetic field was quiet to unsettled on November 5. Solar wind speed ranged between 464 and 596 km/sec.

Solar flux measured at 20h UTC on 2.8 GHz was 114.0. The planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 10.1).
Three hour interval K indices: 21222333 (planetary), 20101233 (Boulder).

The background x-ray flux is at the class B5 level.

At midnight there was 1 spotted region on the visible disk. Solar flare activity was high. A total of 6 C and 2 M class events was recorded during the day. Region 10486 behind the southwest limb continued to be active, particularly during the first half of the day. The region was the source of an M1.6 flare at 02:41 and a major, impulsive M5.3 flare at 10:52 UTC.

Region 10495 decayed slowly and quietly.

Coronal mass ejections (CMEs)

November 4: A fast, large, full halo CME was observed in LASCO C2 images beginning at 12:04 UTC. With no obvious frontside source the source of this CME is likely to have been near the center of the backside, probably in old region 10484.

A huge and very fast full halo CME was observed after the X28 flare in region 10486 at 19:53 UTC. The speed of this CME has been estimated at nearly 2400 km/sec. While the core of the CME will not reach the Earth, the slower flank part could impact Earth on November 6.

November 3 and 5: No partially or fully Earth directed CMEs 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 small and poorly defined coronal hole (CH65) in the northern hemisphere with a trans equatorial extension could rotate into a geoeffective position on November 5-6. A recurrent coronal hole (CH66) will likely reach a geoeffective position on November 9-10.

Processed SOHO/EIT 284 image at 01:06 UTC on November 6. The darkest areas on the solar disk are likely coronal holes.


The geomagnetic field is expected to be quiet to unsettled on November 6 until an expected CME impact some time during the day. After the impact active to minor storm conditions are possible for 6-12 hours. Quiet to unsettled is likely on November 7 with a few unsettled to active intervals possible on November 8-9 due to a high speed stream from coronal hole CH65.

Long distance low frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is poor to very poor. Propagation along long distance north-south paths is poor. [Trans Atlantic propagation conditions are currently monitored every night on 1470 kHz. Dominant station: Radio Cristal del Uruguay. An unidentified North American station on 930 kHz was observed covering an NHL game].

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.
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.

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.

Solar region Date numbered SEC
Location at midnight Area Classification Comment
10487 2003.10.25 7   N11W73 0020 AXX spotless
10494 2003.10.30     S23W70     plage
10495 2003.10.30 5 2 S22W60 0110 CSO  
10496 2003.10.31     S12W56     plage
10497 2003.11.04     N10W58     plage
S294 emerged on
    S09W46     plage
S296 emerged on
    S07W26     plage
S297 emerged on
    N12W19     plage
S298 emerged on
    N13W25     plage
S299 emerged on
    S22W45     plage
Total spot count: 12 2
SSN: 32 12

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)
2002.10 167.0 97.5 90.5 (-4.1)
2002.11 168.7 95.5 85.2 (-5.3)
2002.12 157.2 80.8 82.0 (-3.2)
2003.01 144.0 79.7 80.9 (-1.1)
2003.02 124.5 46.0 78.5 (-2.4)
2003.03 131.4 61.1 74.1 (-4.4)
2003.04 126.4 60.0 70.3 (-3.8)
2003.05 115.7 55.2 (66.8 predicted, -3.5)
2003.06 129.3 77.4 (63.0 predicted, -3.8)
2003.07 127.7 85.0 (59.3 predicted, -3.7)
2003.08 122.1 72.7 (56.3 predicted, -3.0)
2003.09 112.2 48.8 (54.3 predicted, -2.0)
2003.10 151.7 65.6 (51.6 predicted, -2.7)
2003.11 170.0 (1) 21.3 (2) (48.9 predicted, -2.7)

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 sources noted in solar links. All time references are to the UTC day. Comments and suggestions are always welcome.

[DX-Listeners' Club]