Solar Terrestrial Activity Report

Activity chart

Last major update issued on September 16, 2022 at 06:50 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 active on September 15. Solar wind speed at SOHO ranged between 311 and 384 km/sec. The high latitude magnetometer at Andenes recorded quiet to minor storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 139.7 - increasing 34.3 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 111.78). The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 5.9). Three hour interval K indices: 41101211 (planetary), 41112321 (Boulder), 51011200 (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 10 active regions using 2K resolution (SN: 190) and in 7 active regions using 1K resolution (SN: 111) SDO/HMI images.

Region 13096 [N18W42] decayed slowly and quietly.
Region 13098 [N19W78] decayed slowly and was much less active than during the previous days. C1 flares: C1.5 @ 02:35, C1.5 @ 11:36, C1.6 @ 17:00, C1.7 @ 21:44, C1.7 @ 23:34 UT
Region 13100 [S20W20] decayed slowly and quietly.
Region 13102 [S27E35] was mostly quiet and stable.
New region 13103 [S16E07] was first observed on September 10 with SWPC numbering the region 5 days later as new flux emerged. Many spots formed and the region is fairly compact with what may be a weak magnetic delta in the central northern part.

Spotted regions not observed (or interpreted differently) by SWPC:
S7843 [N13W38] was quiet and stable.
S7858 [N13W76] decayed slowly and quietly.
S7869 [N27W02] decayed slowly and quietly.
S7870 [N12W12] was quiet and stable.
New region S7872 [S20E60] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C3.8 03:19   13098 GOES16  
C6.4 06:33 behind NW limb 13101 GOES16 LDE
C2.1 14:31 behind NW limb 13101 GOES16  
C2.3 19:21   13098 GOES16  

Coronal mass ejections (CMEs)

September 13-15: 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) rotated 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 to fair.

Forecast

Quiet to active conditions are likely on September 16-18 when a high speed stream from CH1099 could 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
13096 2022.09.05
2022.09.06
  2   N18W47 0003   AXX

 

location: N18W42

S7842 2022.09.05       S23W54            
S7843 2022.09.06   3 2 N15W38 0010   CRO  
13098 2022.09.06
2022.09.08
10 12 7 N19W76 0560 EHC ESI

location: N19W78

13100 2022.09.08
2022.09.10
9 23 9 S23W20 0160 CSO CSO

 

13099 2022.09.09
2022.09.10
      N12W38            
S7854 2022.09.09       S16W51            
S7858 2022.09.10   2   N13W76 0002   BXO  
13103 2022.09.10 7 29 14 S16E06 0030 CRO DRI beta-gamma

area: 0080

S7861 2022.09.10       S02W32            
S7862 2022.09.11       S18W08          
S7863 2022.09.11       S21W26            
13102 2022.09.12
2022.09.13
5 15 7 S26E38 0250 DKO EAO location: S27E35
S7867 2022.09.13       N31W18            
S7869 2022.09.14   1 1 N27W02 0003   AXX  
S7870 2022.09.14   2   N12W12 0003   BXO  
S7871 2022.09.14       S03W45          
S7872 2022.09.15   1 1 S20E60 0003   AXX    
Total spot count: 31 90 41  
Sunspot number: 71 190 111  (total spot count + 10 * number of spotted regions)
Weighted SN: 59 111 62  (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): 78 105 89  

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
2022.09 133.9 (1)   40.5 (2A) / 81.1 (2B) / 102.9 (2C) (104.9 projected, +4.9) (16.4)
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.