Last major update issued on June 8, 2004 at 04:05 UTC.
[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update June 2, 2004)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update June 2, 2004)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update June 2, 2004)]
[Historical solar and geomagnetic data charts 1954-2004 (last update April 28, 2004)]
[Archived reports (last update June 7, 2004)]
The geomagnetic field was quiet to unsettled on June 7. Solar wind speed ranged between 410 and 481 km/sec.
Solar flux measured at 20h UTC on 2.8 GHz was 88.5. The planetary A
index was 8 (STAR Ap - based on the mean of three hour interval ap indices: 9.4).
Three hour interval K indices: 31223223 (planetary), 22222223 (Boulder).
The background x-ray flux is at the class A6 level.
At midnight there were 6 spotted regions on the visible disk. The solar flare activity level was low. A single C class event was recorded during the day.
Region 10621 was mostly unchanged. Flare: C2.7 long duration event
peaking at 00:44 UTC.
Region 10627 decayed slightly in the leading spot section while the trailing spots developed slowly.
New region 10628 emerged early in the day in the southeast quadrant.
New region 10629 emerged in the southeast quadrant.
New region 10630 rotated into view on June 6 at the northeast limb and was numbered the next day by SEC.
Spotted regions not numbered by NOAA/SEC:
[S414] This region emerged in the southeast quadrant just west of region 10629 on June 7. Location at midnight: S03E14.
June 5-6: No fully or partly Earth directed CMEs observed.
June 7: At least a partial halo CME was associated with a long duration C2 event in region 10621 early in the day. This CME could reach Earth on June 10.
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.
Processed SOHO/EIT 284 image at 13:05 UTC on June 76. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to unsettled on June 8-10 with a possibility of a few active intervals on June 10 if the CME noted above reaches Earth..
|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.
Long distance low and medium 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 good. Trans Atlantic propagation conditions are monitored every night on 1470 kHz. Dominant stations tonight: Radio Cristal del Uruguay most of the time, Radio Vibración (Venezuela) was the best after local sunrise. Propagation favored Brazil and in particular the central southern parts. Rádio Itatiaia on 610 was a surprise and Rádio Joven Pan in Brasilia on 750 kHz had a good signal. Rádio Nacional on 980 in Brasilia was excellent at times. I noted an interesting Brazilian on 1540 kHz as well and may have recorded an ID. The only stations from North America were the dominants on 1510, 1650 and 1660 kHz.
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 HRX
classification was CRO
|10630||2004.06.07||2||1||N13E56||0010||AXX||formerly region S413|
|Total spot count:||22||16|
flux at Earth
|International sunspot number||Smoothed sunspot number|
cycle 23 sunspot max.
|2003.12||114.9||46.5||(54.4 predicted, -2.3)|
|2004.01||114.1||37.2||(50.5 predicted, -3.9)|
|2004.02||107.0||46.0||(46.2 predicted, -4.3)|
|2004.03||112.0||48.9||(43.5 predicted, -2.7)|
|2004.04||101.2||39.3||(41.4 predicted, -2.1)|
|2004.05||99.8||41.5||(38.2 predicted, -3.2)|
|2004.06||88.7 (1)||15.7 (2)||(35.3 predicted, -2.9)|
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.