Last major update issued on July 3, 2006 at 02:25 UTC.
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(last update June 7, 2006)]
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[Historical solar and
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June 5, 2006)]
The geomagnetic field was inactive to quiet on July 2. Solar wind speed ranged between 333 and 430 km/s (all day average 361 km/s - decreasing 82 km/s from the previous day).
Solar flux measured at 20h UTC on 2.8 GHz was 87.1. The planetary A index
was 2 (STAR Ap - based on the mean of three hour interval ap
indices: 2.5).
Three hour interval K indices: 10001201 (planetary), 10011101 (Boulder).
The background x-ray flux is at the class A6 level.
At midnight there were 2 spotted regions on the visible solar disk. The solar flare activity level was very low. No C class events were recorded during the day.
Region 10897 lost penumbra on the main spot, however, there a still
several small spots in this region.
Region 10898 was mostly unchanged. C flares are possible.
June 30 - July 2: No partly or fully Earth directed CMEs were detected in incomplete LASCO imagery.
Coronal hole history (since late October 2002)
Compare today's report to the situation one solar rotation ago:
28 days ago
27 days ago
26 days ago
A recurrent trans equatorial coronal hole (CH230) was in an Earth facing position on July 1-3.
Processed SOHO/EIT 284 image at 19:06 UTC on July 2. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be mostly quiet on July 3 and become unsettled to minor storm July 4-6 due to a high speed stream from CH230.
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) Effects from a CME are likely to be observed at 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. Propagation on long distance northeast-southwest paths is good. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Radio Cristal del Uruguay was the most frequently heard station, however, listening was very difficult because of an intense thunderstorm over the Bay of Biscaye. Only a few strong signals could be identified. Rádio Globo on 1220 kHz was very strong at S9+20dB while 1030 Radio del Plata and 1190 Radio América (both Argentina) were strong.
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 |
---|---|---|---|---|---|---|---|
10897 | 2006.06.25 | 1 | 5 | N06W23 | 0020 | BXO | |
10898 | 2006.06.28 | 13 | 12 | S06E14 | 0290 | CHO | classification was DKO at midnight |
S666 | 2006.06.28 | N05W30 | plage | ||||
Total spot count: | 14 | 17 | |||||
SSN: | 34 | 37 |
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) |
2005.05 | 99.3 | 42.7 | 28.9 (-2.7) |
2005.06 | 93.7 | 39.3 | 28.8 (-0.1) |
2005.07 | 96.4 | 40.1 | 29.1 (+0.3) |
2005.08 | 90.5 | 36.4 | 27.4 (-1.7) |
2005.09 | 91.1 | 21.9 | 25.8 (-1.6) |
2005.10 | 77.0 | 8.5 | 25.5 (-0.3) |
2005.11 | 86.3 | 18.0 | 24.9 (-0.6) |
2005.12 | 90.7 | 41.2 | 23.0 (-1.9) |
2006.01 | 83.4 | 15.4 | (20.7 predicted, -2.3) |
2006.02 | 76.5 | 4.7 | (18.2 predicted, -2.5) |
2006.03 | 75.4 | 10.8 | (16.4 predicted, -1.8) |
2006.04 | 89.0 | 30.2 | (15.7 predicted, -0.7) |
2006.05 | 80.9 | 22.2 | (14.9 predicted, -0.8) |
2006.06 | 76.5 | 13.9 | (12.7 predicted, -2.2) |
2006.07 | 86.3 (1) | 2.3 (2) | (11.3 predicted, -1.4) |
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% lower.
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.
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