Solar Terrestrial Activity Report

Activity chart

Last major update issued on September 13, 2022 at 12:35 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 (September 1, 2022)
Solar cycle Solar cycles 23-25 (September 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (September 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 (September 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (September 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 unsettled on September 12. Solar wind speed at SOHO ranged between 349 and 427 km/sec. The high latitude magnetometer at Andenes recorded quiet to active levels.

Solar flux density measured at 20h UT on 2.8 GHz was 150.4 - increasing 21.9 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 111.22). The Potsdam WDC planetary A index was 7 (STAR Ap - based on the mean of three hour interval ap indices: 7.3). Three hour interval K indices: 33321011 (planetary), 23332311 (Boulder), 43323220 (Andenes).

The background x-ray flux is at the class C2 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 15 active regions using 2K resolution (SN: 327) and in 13 active regions using 1K resolution (SN: 211) SDO/HMI images.

Region 13092 [S10W80] was quiet and stable.
Region 13096 [N18W05] decayed slowly and quietly.
Region 13097 [S12W68] developed further and was quiet.
Region 13098 [N19W38] developed further and could produce M class flares.
Region 13099 [N11E05] was quiet and stable.
Region 13100 [S24E22] was mostly quiet and stable, the magnetic layout is fairly simple.
Region 13101 [N29W83] developed further and rotated partly out of view. The region produced many C flares and could manage M class flares while at and just behind the northwest limb.

Spotted regions not observed (or interpreted differently) by SWPC:
S7842 [S26W16] was quiet and stable.
S7843 [N12W02] was quiet and stable.
S7857 [N24W32] was quiet and stable.
S7858 [N15W35] was quiet and stable.
S7860 [S17E48] was quiet and stable.
S7862 [S18E32] developed slowly and quietly.
New region S7865 [S27E76] rotated into view with a large mature leader spot.
New region S7866 [N11W35] emerged with tiny spots.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.8 00:28   13098 GOES16  
C2.4 00:45   13098 GOES16  
C2.6 02:01   13098 GOES16  
C2.6 02:29   13101 GOES16  
C3.2 03:19   13101 GOES16  
C2.1 04:16   13101 GOES17  
C2.9 05:33   13098 GOES17  
C3.0 06:09   13101 GOES16  
C4.5 06:30   13101 GOES16  
C2.5 07:10   13101 GOES16  
C2.6 08:01 southeast limb S7865 GOES16  
C2.3 08:34   13101 GOES16 Incorrectly attributed to AR 13098 by SWPC
C3.7 09:25   13101 GOES16  
C3.5 10:17   13101 GOES16  
C3.5 11:27 N28W76 13101 GOES16  
C6.3 12:25   13098 GOES16 Incorrectly attributed to AR 13101 by SWPC
C7.4 13:00 N29W77 13101 GOES16  
C2.0 15:32   13101 GOES16  
C2.0 16:17   13101 GOES16  
C5.2 19:03 N21W34 13098 GOES16  
C2.7 19:29 southeast limb S7865 GOES16  
C3.6 19:56 N29W81 13101 GOES16  
C3.1 20:51   13101 GOES16  
C2.9 21:34   13101 GOES16  
C2.4 23:21   13098 GOES16  
M1.7 23:44 N19W40 13098 GOES16  

Coronal mass ejections (CMEs)

September 10-12: 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 northern hemisphere coronal hole (CH1099) will rotate across the central meridian on September 13-14.

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.

Forecast

Quiet to unsettled conditions are expected on September 13-14 due to effects from CH1098. Quiet conditions are likely on September 15 becoming quiet to active on September 16-17 when a high speed stream from CH1099 is likely to reach Earth.

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
13092 2022.08.31
2022.09.01
1 1 1 S10W80 0030 HSX HSX

area: 0070

13094 2022.09.02
2022.09.02
1     N20W55 0010 AXX     location: N19W53

spotless

13097 2022.09.05
2022.09.07
6 18 9 S11W69 0020 DRO DRI

location: S12W68

S7840 2022.09.05       N17W48            
13096 2022.09.05
2022.09.06
1 10 7 N16W09 0000 AXX CRO

location: N18W05

area: 0020

S7842 2022.09.05   3   S26W16 0005   BXO  
S7843 2022.09.06   11   N12W02 0018   BXO  
13098 2022.09.06
2022.09.08
12 43 24 N18W36 0160 EAC EKC beta-gamma-delta

area: 0560

location: N19W38

S7845 2022.09.06       S09W21            
S7848 2022.09.07       S24W48            
13100 2022.09.08
2022.09.10
10 35 19 S24E25 0060 DSO ESI

location: S24E22

area: 0190

13099 2022.09.09
2022.09.10
1 6 2 N11E05 0000 AXX CRO area: 0010
S7853 2022.09.09       S04W22            
S7854 2022.09.09       S16W12            
13101 2022.09.10
2022.09.10
5 12 9 N29W83 0090 DSO EAI

area: 0250

S7857 2022.09.10   4 2 N24W32 0010   CRO  
S7858 2022.09.10   12 6 N15W35 0025   CRO  
S7860 2022.09.10   10 5 S17E48 0020   BXO  
S7861 2022.09.10       S02E07            
S7862 2022.09.11   4 3 S18E32 0010   BXO  
S7863 2022.09.11       S21E13          
S7864 2022.09.11       S21W36          
S7865 2022.09.12   4 2 S27E76 0330   EKO    
S7866 2022.09.12   4 2 N11W35 0010   BXO    
Total spot count: 37 177 92  
Sunspot number: 117 327 222  (total spot count + 10 * number of spotted regions)
Weighted SN: 60 227 142  (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): 129 180 178  

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
2021.02 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 64.8 (+4.7) 10.46
2022.03 117.0 115.8 78.6 (68.7 projected, +3.9) 10.20
2022.04 130.8 131.7 84.1 (73.9 projected, +5.2) 11.79
2022.05 133.8 136.8 96.5 (80.3 projected, +6.4) 7.48
2022.06 116.1 119.8 70.5 (86.2 projected, +5.9) 8.20
2022.07 125.4 129.5 91.4 (93.4 projected, +7.2) 9.51
2022.08 114.2 117.1 75.4 (100.0 projected, +6.6) 10.92
2022.09 130.9 (1)   32.5 (2A) / 81.3 (2B) / 107.5 (2C) (104.9 projected, +4.9) (19.1)
2022.10       (108.1 projected, +3.2)  
2022.11       (110.9 projected, +2.8)  
2022.12       (115.7 projected, +4.8)  
2023.01       (121.7 projected, +6.0)  
2023.02       (126.7 projected, +5.0)  
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.