Solar Terrestrial Activity Report

Activity chart

Last major update issued on August 30, 2022 at 15:00 UT.

Charts (* = updated daily) Data and archive
  Solar wind (*) Solar and geomagnetic data - last month (*)
  Electron fluence (*) Archived daily reports and monthly data since 2003.01 (August 7, 2022)
Solar cycle Solar cycles 23-25 (August 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (August 1, 2022) Noon SDO sunspot count 1K image / 4K (*)
  Solar cycles 1-24 (July 1, 2020) POES auroral activity level [October 2009 - December 2012]
  Comparison of cycles 21-25 (August 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (August 1, 2022) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (August 21, 2022) Cycle 25 spots (final update December 25, 2019)
  Solar cycles 24-25 transition using 365d smoothing Research: Solar Cycle 25 Started on November 17, 2019 with 365 Days Smoothing

Recent activity

The geomagnetic field was quiet to active on August 29 under the combined effects of CH1096 and a CME. Solar wind speed at SOHO ranged between 385 and 581 km/sec. The high latitude magnetometer at Andenes recorded quiet to active levels.

Solar flux density measured at 23h UT on 2.8 GHz was 130.6 - increasing 38.1 over the previous solar rotation (the measurements at 17 and 20h UT were flare enhanced). (Centered 1 year average SF at 1 AU - 183 days ago: 109.65). The Potsdam WDC planetary A index was 7 (STAR Ap - based on the mean of three hour interval ap indices: 6.9). Three hour interval K indices: 21132221 (planetary), 21233322 (Boulder), 34333132 (Andenes).

The background x-ray flux is at the class C1 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 9 active regions using 2K resolution (SN: 171) and in 5 active regions using 1K resolution (SN: 91) SDO/HMI images.

Region 13085 [N30W87] decayed slowly and quietly.
Region 13086 [S23W39] decayed slowly and quietly.
Region 13087 [S15W12] was mostly quiet and stable.
Region 13089 [S22E05] was mostly inactive despite a magnetic delta in the trailing spot section. A major flare is possible.
Region 13090 [N17E09] was quiet and stable.

Spotted regions not observed (or interpreted differently) by SWPC:
S7817 [S21W30] was quiet and stable.
S7822 [N25E60] was quiet and stable.
New region S7823 [N07E56] was observed with a tiny spot in an old plage area.
New region S7824 [S12E36] emerged with tiny spots.

AR 13088 produced many C and M flares while at and behind the southwest limb.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C3.3 01:23   13088 GOES16  
C3.9 02:02   13088 GOES16  
C3.7 02:49 S23W80 13088 GOES16  
M3.3 03:38 S23W80 13088 GOES16  
C3.4 04:54   13088 GOES16  
C4.7 05:43   13088 GOES16  
C3.7 06:40   13088 GOES16  
C4.0 06:50   13088 GOES16  
C8.5 09:10   13088 GOES16  
M8.6 11:08 behind SW limb 13088 GOES16  
C2.6 13:08   13088 GOES16  
C2.5 13:25   13088 GOES16  
C8.7 14:40   13087 GOES16 LDE
M2.5 14:56   13088 GOES16 LDE
M4 estimated 16:35   13088 estimated from data before and after the peak  
M4.7 18:57   13088 GOES17  
C6.0 21:54   13088 GOES17  
C3.9 22:48   13088 GOES17  
C3.8 23:40   13088 GOES17  

Coronal mass ejections (CMEs)

August 27: A partial halo CME was observed after the M4.8 LDE in AR 13088 early in the day.
August 28-29: No obviously Earth directed CMEs were observed.

Coronal holes

[Coronal hole history (since October 2002)]
[Compare today's report to the situation one solar rotation ago: 28 days ago 27 days ago 26 days ago]

A southern hemisphere coronal hole (CH1096) rotated across the central meridian on August 25-27.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle and high latitudes is poor. Propagation on long distance northeast-southwest paths is poor to fair.

Forecast

Quiet to active conditions are possible on August 30 due to effects from CH1096 and CME effects. Quiet to unsettled is expected for August 31 - September 2.

Coronal holes (1) Coronal mass ejection (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: 0-30% probability, Yellow: 30-70% probability, Red: 70-100% probability.

Active solar regions


(Click on image for 2K resolution). 4K resolution. Compare to the previous day's image.
0.5K image

When available the active region map has a coronal hole polarity overlay where red (pink) is negative and blue is positive.

Data for all officially numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC, all other regions are numbered sequentially as they emerge using the STAR spot number. 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 SWPC or where SWPC has observed no spots. SWPC active region numbers in the table below and in the active region map above are the historic SWPC/USAF numbers. SWPC data considered to be not sufficiently precise (location, area, classification) are colored red.

Active region SWPC date numbered
STAR detected
Spot count Location at midnight Area Classification SDO / HMI 4K continuum
image with magnetic polarity overlays
Comment
SWPC/
USAF
Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
13085 2022.08.20
2022.08.21
1 3 2 N31W90 0060 HSX HAX

 

13086 2022.08.21
2022.08.23
2 7 4 S24W38 0030 DSO BXO location: S23W39
S7803 2022.08.21       N20W38            
S7804 2022.08.21       N28W55            
S7806 2022.08.22       N08W53            
13087 2022.08.22
2022.08.23
1 6 2 S14W13 0010 AXX AXX  
13090 2022.08.23
2022.08.25
  7   N16E06 0012   BXO location: N17E09
13088 2022.08.24
2022.08.25
4     S27W95 0250 DKC    

rotated out of view early in the day

13089 2022.08.24 29 49 32 S22E06 0580 EKC EKC beta-gamma-delta

location: S22E05

S7811 2022.08.25       N13W41            
S7813 2022.08.25       N03W51            
S7814 2022.08.25       N34W32            
S7815 2022.08.26       S22W31            
S7816 2022.08.26       S13E37            
S7817 2022.08.27   4 1 S21W30 0008   BXO  
S7818 2022.08.27       N11W21            
S7819 2022.08.27       N09W23            
S7820 2022.08.28       S03W34          
S7821 2022.08.28       N15E25          
S7822 2022.08.28   2   N25E60 0002   AXX  
S7823 2022.08.29   1   N07E56 0003   AXX    
S7824 2022.08.29   2   S12E36 0005   AXX    
Total spot count: 37 81 41  
Sunspot number: 87 171 91  (total spot count + 10 * number of spotted regions)
Weighted SN: 67 96 56  (Sum of total spot count + classification weighting for each AR. Classification weighting: X=0, R=3, A/S=5, H/K=10)
Relative sunspot number (Wolf number): 96 94 73  

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2014.02 170.3
(cycle peak)
166.3 146.1 (SC24 peak) 110.5 10.70
2014.04 143.9 144.8 112.5 116.4 (solar max) 7.88
2017.09 91.3 92.3 43.6 18.2 (-1.3) 18.22
(cycle peak)
2019.11 70.2 68.7 0.5 2.0 (-0.6)
(Solar minimum using 365d smoothing:
November 17, 2019)
4.19
2019.12 70.8 68.6 1.6 1.8 (-0.2)
(ISN 13 months smoothed
solar minimum)
3.22
2021.01 76.0 73.6 10.4 17.3 (+2.0) 4.39
2021.02 74.3 72.4 8.2 19.0 (+1.7) 9.50
2021.03 76.0 75.2 17.2 21.7 (+2.7) 10.17
2021.04 75.9 76.4 24.5 24.8 (+3.1) 8.40
2021.05 75.3 77.1 21.2 25.8 (+1.0) 6.50
2021.06 79.4 81.8 25.0 27.6 (+1.8) 5.52
2021.07 81.0 83.6 34.3 31.4 (+3.8) 5.51
2021.08 77.7 79.7 22.0 35.4 (+4.0) 6.19
2021.09 87.0 88.2 51.3 40.2 (+4.8) 6.33
2021.10 88.9 88.3 37.4 45.2 (+5.0) 7.38
2021.11 86.2 84.4 34.8 50.8 (+5.6) 9.83
2021.12 103.0 99.8 67.5 55.9 (+5.1) 6.40
2022.01 103.8 100.5 55.3 60.1 (+4.2) 8.92
2022.02 109.1 106.5 60.9 (65.8 projected, +5.7) 10.46
2022.03 117.0 115.8 78.6 (70.8 projected, +5.0) 10.20
2022.04 130.8 131.7 84.1 (75.9 projected, +5.1) 11.79
2022.05 133.8 136.8 96.5 (82.4 projected, +6.5) 7.48
2022.06 116.1 119.8 70.5 (88.3 projected, +5.9) 8.20
2022.07 125.4 129.5 91.4 (95.5 projected, +7.2) 9.51
2022.08 113.9 (1)   66.5 (2A) / 71.1 (2B) / 94.6 (2C) (102.0 projected, +6.5) (10.9)
2022.09       (106.9 projected, +4.9)  
2022.10       (110.1 projected, +3.2)  
2022.11       (112.9 projected, +2.8)  
2022.12       (117.7 projected, +4.8)  
2023.01       (123.7 projected, +6.0)  
2023.11       (142.5 projected max SC25)  

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz and any corrections applied to that measurement.
2A) Current impact on the monthly sunspot number based on the Boulder (NOAA/SWPC) sunspot number (accumulated daily sunspots / month days).
2B) Boulder SN current month average to date.
2C) STAR SDO 1K Wolf number 30 day average.
3) Running average based on the quicklook and definitive Potsdam WDC ap indices. Values in red are based on the definitive international GFZ Potsdam WDC ap indices.
4) Source: SIDC-SILSO.

Solar cycles 24-25

Smoothed SF and sunspot numbers

 

This report has been prepared by Jan Alvestad. It is based on the analysis of data from whatever sources are available at the time the report is prepared. All time references are to Universal Time. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.