Solar Terrestrial Activity Report

Last major update issued on November 28, 2003 at 04:20 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 22, 2003)]

Recent activity

The geomagnetic field was quiet to unsettled on November 27. Solar wind speed ranged between 400 and 527 km/sec, gradually decreasing all day.

Solar flux measured at 20h UTC on 2.8 GHz was 174.7. The planetary A index was 10 (STAR Ap - based on the mean of three hour interval ap indices: 10.1).
Three hour interval K indices: 22223333 (planetary), 22122233 (Boulder).

The background x-ray flux is at the class B6 level.

At midnight there were 11 spotted regions on the visible disk. Solar flare activity was low. A total of 7 C class events were recorded during the day.

Region 10507 decayed further losing penumbral area and spots. An isolated M class flare is possible as there is still a magnetic delta structure in the northern part of the largest penumbra.
Region 10508 decayed moderately quickly. Flares: C1.1 at 02:02, C1.9 at 06:46, C9.6 long duration event peaking at 08:20 (this event extended into region 10514 and was associated with a small and slow CME moving off of the southwest limb) and C2.7 at 18:47 UTC.
Region 10509 developed slowly and was mostly quiet. Flare: C2.2 at 00:29 UTC.
Region 10510 developed in the leading spot section while decay was observed elsewhere. Flare: C1.2 at 22:10 UTC.
Region 10511 decayed slowly and was quiet.
Region 10512 decayed and could soon become spotless. Flare: C3.2 at 12:26 UTC.
Region 10513 was quiet and stable.
New region 10514 emerged in the southwest quadrant on November 26 and was numbered the next day by SEC. The region appears to be decaying and could soon become spotless.

Spotted regions not numbered by NOAA/SEC:
[S314] A new region emerged in the southeast quadrant on November 27 to the north of region 10510. Location at midnight: S15E23.
[S315] This region rotated into view at the southeast limb late on November 27. Location at midnight: S16E80.
[S316] This region rotated into view at the southeast limb near the equator late on November 27. Location at midnight: S03E79.

Coronal mass ejections (CMEs)

November 25-27: No partly 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

No obvious coronal holes are currently approaching geoeffective positions. The southernmost extensions of the northern polar coronal hole could be marginally geoeffective.

Processed SOHO/EIT 284 image at 01:05 UTC on November 28. The darkest areas on the solar disk are likely coronal holes.

Forecast

The geomagnetic field is expected to be quiet to unsettled on November 28 - December 2.

Long distance low 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 currently monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay and Cadena Peruana de Noticias].

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.

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
10505 2003.11.17     S22W73     plage
10506 2003.11.18 1   S23W43 0000 AXX spotless
10507 2003.11.18 14 22 N07W43 0540 DKI beta-gamma-delta
classification was DKC
at midnight
10508 2003.11.19 16 29 S18W31 0180 DAO classification was DAI
at midnight
10509 2003.11.24 6 8 S11E15 0050 DSO classification was CAO
at midnight, area 0080
10510 2003.11.24 13 31 S23E24 0080 CSO classification was DAI
at midnight
10511 2003.11.25 6 17 S15W02 0050 DSO  
10512 2003.11.25 6 7 N06E04 0030 CSO  
10513 2003.11.26 1 1 N13E58 0050 HSX  
10514 2003.11.27 1 2 S16W46 0000 AXX formerly region S313
S314 emerged on
2003.11.27
  2 S15E23 0010 BXO  
S315 visible on
2003.11.27
  1 S16E80 0040 HSX  
S316 visible on
2003.11.27
  1 S03E79 0010 AXX  
Total spot count: 64 121
SSN: 154 231

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)
2003.11 138.4 (1) 85.0 (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]