Last major update issued on March 6, 2004 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 March 2, 2004)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update March 2, 2004)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update March 2, 2004)]
[Historical solar and geomagnetic data charts 1954-2003 (last update January 16, 2004)]
[Archived reports (last update March 3, 2004)]
The geomagnetic field was quiet to unsettled on March 5. Solar wind speed ranged between 399 and 462 km/sec.
Solar flux measured at 20h UTC on 2.8 GHz was 106.7. The planetary A
index was 8 (STAR Ap - based on the mean of three hour interval ap indices: 9.1).
Three hour interval K indices: 21322232 (planetary), 02321122 (Boulder).
The background x-ray flux is at the class B3 level.
At midnight there were 3 spotted regions on the visible disk. Solar flare activity was low. A total of 3 C class events was recorded during the day.
Region 10567 decayed slowly in the leading and trailing spot sections while slow development occurred in the central
section where there is little separation between the opposite polarity areas.
Region 10569 developed slowly and quietly.
New region 10570 rotated into view at the southeast limb revealing a large penumbra. Magnetograms indicate the presence of both negative and positive polarity areas within that penumbra, however, the region will have to rotate into better view to determine if there actually is a magnetic delta structure. M class flares are possible.
March 3-5: No partly or fully earth directed CMEs observed.
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 recurrent coronal hole (CH84) mostly in the northern hemisphere will likely reach a geoeffective position on March 7-10.
Processed SOHO/EIT 284 image at 01:06 UTC on March 6. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to unsettled on March 6-9 and unsettled to minor storm on March 10-11 due to a high speed stream from coronal hole CH84.
Long distance low and medium frequency (below 2 MHz) propagation along east-west paths over high and upper middle latitudes is poor. Propagation along long distance north-south paths is poor. [Trans Atlantic propagation conditions are currently monitored every night on 1470 kHz. Dominant station tonight: Radio Vibración (Venezuela). Only a few other, weak signals were detected at 03h UTC, conditions had improved by 04h UTC when the most common stations from Florida were noted].
|Coronal holes (1)||Coronal mass ejections (2)||M and X class flares (3)|
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.
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|
classification was EAI
at midnight, area 0200
classification was DAO
at midnight, area 0070
area was 0300
|Total spot count:||25||43|
flux at Earth
|International sunspot number||Smoothed sunspot number|
cycle 23 sunspot max.
|2003.09||112.2||48.7||(58.9 predicted, -1.1)|
|2003.10||151.7||65.5||(56.2 predicted, -2.7)|
|2003.11||140.8||67.3||(53.5 predicted, -2.7)|
|2003.12||114.9||46.5||(50.9 predicted, -2.6)|
|2004.01||114.1||37.2||(46.7 predicted, -4.2)|
|2004.02||107.0||46.0||(42.1 predicted, -4.6)|
|2004.03||99.0 (1)||8.6 (2)||(39.7 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% 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.