Last major update issued on August 3, 2005 at 04:30 UTC.
geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 21-23 (last update August 2, 2005)]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22 and 23 (last update August 2, 2005)]
[Graphical comparison of cycles 2, 10, 13, 17, 20 and 23 (last update August 2, 2005)]
[Historical solar and geomagnetic data charts 1954-2004 (last update February 1, 2005)]
[Archived reports (last update August 3, 2005)]
The geomagnetic field was quiet to unsettled on August 2. Solar wind speed ranged between 430 and 621 (all day average 486) km/sec.
Solar flux measured at 20h UTC on 2.8 GHz was 110.2. The planetary
index was 12 (STAR Ap - based on the mean of three hour interval ap
Three hour interval K indices: 33233222 (planetary), 33233322 (Boulder).
The background x-ray flux is at the class B2 level.
At midnight there were 4 spotted regions on the visible solar disk. The solar flare activity level was moderate. A total of 3 C and 1 M class events was recorded during the day.
Region 10792 decayed significantly in the northeast and southwest sections. An M class flare is possible. Flare:
C6.7 at 20:16 UTC.
Region 10793 decayed and could become spotless later today.
Region 10794 has been unstable and could produce another minor M class flare. Flares: C2.9 at 07:46, C8.7 at 12:45, M4.2/1N at 18:31 UTC (associated with a strong type II and a weak type IV radio sweep).
Region 10795 was quiet and stable.
July 31 - August 2: No obvious partly or fully Earth directed CMEs were observed.
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 in or near Earth facing positions.
Processed SOHO/EIT 284 image at 01:06 UTC on August 3. The darkest areas on the solar disk are likely coronal holes.
The geomagnetic field is expected to be quiet to unsettled on August 3- with an isolated active interval possible on the first day.
|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 fair. Propagation on long distance northeast-southwest paths is poor to fair. Trans Atlantic propagation conditions are normally monitored every night on 1470 kHz. Dominant stations tonight: Radio Vibración (Venezuela) and Radio Cristal del Uruguay. After LSR some stations from Uruguay and Argentina could be heard on frequencies like 1430, 1480, 1490, 1500 and 1510 kHz. Radio Rural (Uruguay) on 610 was unusually strong. Before LSR many stations from the easternmost parts of the USA and Canada were heard. Most of the usual Newfoundland, Nova Scotia and New Brunswick stations had fair signals. While WWZN on 1510 kHz had the strongest signal, New York stations on 880, 1050 and 1130 kHz were quite good. WBAE Portland ME on 1490 kHz was audible as well.
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|
|10791||2005.07.23||1||N12W88||0060||HSX||rotated out of view|
classification was DAI at midnight, area 0220
classification was CRO at midnight, area 0010
|Total spot count:||62||49|
flux at Earth
|International sunspot number||Smoothed sunspot number|
cycle 23 sunspot max.
|2005.02||97.2||29.1||(33.5 predicted, -1.1)|
|2005.03||89.9||24.8||(32.1 predicted, -1.4)|
|2005.04||86.0||24.4||(30.2 predicted, -1.9)|
|2005.05||99.3||42.6||(27.6 predicted, -2.6)|
|2005.06||93.7||39.3||(26.1 predicted, -1.5)|
|2005.07||96.4||39.9||(25.1 predicted, -1.0)|
|2005.08||110.7 (1)||6.9 (2)||(23.2 predicted, -1.9)|
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% 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.