Solar Terrestrial Activity Report

Activity chart

Last major update issued on October 1, 2022 at 10:00 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 (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 30. Solar wind speed at SOHO ranged between 401 and 596 km/sec. The high latitude magnetometer at Andenes recorded quiet to active levels. A high speed stream related to CH1103 was observed arriving at DSCOVR before 04h UT.

Solar flux density measured at 20h UT on 2.8 GHz was 137.1 - increasing 13.7 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 113.91). The Potsdam WDC planetary A index was 13 (STAR Ap - based on the mean of three hour interval ap indices: 13.3). Three hour interval K indices: 34434211 (planetary), 23333220 (Boulder), 43333323 (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 13 active regions using 2K resolution (SN: 214) and in 10 active regions using 1K resolution (SN: 136) SDO/HMI images.

Region 13105 [S18W68] decayed slowly and quietly.
Region 13107 [S24W56] decayed slowly and was mostly quiet.
Region 13110 [N16W23] was quiet and stable.
Region 13111 [N27E31] gained a few spots and produced a few flares during the latter half of the day.
New region 13112 [N19E77] rotated into view with a mature spot.
New region 13113 [N16W14] emerged on September 29 and developed quickly on September when the region was numbered by SWPC. The leading spot of the group is partly inside what was the trailing spot section of AR 13110. Many small spots developed in that section due to the development of AR 13113, and because of the proximity those spots are counted as part of AR 13113.

Spotted regions not observed (or interpreted differently) by SWPC:
S7893 [S15W09] developed slowly early in the day, then decayed.
S7897 [N31E10] was quiet and stable.
New region S7898 [S33E38] emerged with several spots.
New region S7900 [S26W11] emerged with tiny spots.
New region S7901 [N22E82] rotated into view with several spots in a magnetically complex layout. Further M class flaring is likely.
New region S7902 [N28E82] rotated into view with a tiny spot.
New region S7903 [S12E35] was observed with tiny spots in an old plage area.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.0 00:23 northeast limb S7901 GOES16  
C2.8 02:01 northeast limb S7901 GOES16  
C2.8 03:27 northeast limb S7901 GOES16  
M1.0 04:01 northeast limb S7901 GOES16  
C5.2 04:30 N15W15 S7895 GOES16  
C5.3 04:44 northeast limb S7901 GOES16  
C2.7 06:00 northeast limb S7901 GOES16  
C5.5 07:05 northeast limb S7901 GOES16  
C3.1 07:37 northeast limb S7901 GOES16  
C2.8 08:51 northeast limb S7901 GOES16  
C2.3 09:15 northeast limb S7901 GOES16  
C3.0 11:38 N21E90 S7901 GOES16  
C3.1 12:00 N23E90 S7901 GOES16  
C7.8 14:16 N23E89 S7901 GOES16  
C4.0 15:14 N23E88 S7901 GOES16  
C4.1 15:34 N23E88 S7901 GOES16  
M2.9 16:22 N21E87 S7901 GOES16  
M1.3 17:34 N24E87 S7901 GOES16  
C5.8 18:04 N15W22 S7895 GOES16  
C2.1 20:38 N22E84 S7901 GOES16  
C2.4 21:02 N24E84 S7901 GOES16  
C2.1 22:13   S7901 GOES16  
C3.4 22:43   13111 GOES16  
C3.1 23:39   S7901 GOES16 simultaneous flare in AR 13111

Coronal mass ejections (CMEs)

September 29-30: No obviously Earth directed CMEs were observed.
September 28: A filament eruption near the eastern part of AR 13110 began erupting just before 03 UT with the peak of the eruption near 04 UT. A partial halo CME was observed in LASCO imagery, and this CME could reach Earth on October 1.

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]

Recurrent coronal holes (CH1103/CH1104) will be Earth facing on September 27 - October 1.

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 minor storm conditions are likely on October 1-4 due to effects from CH1103 and CH1104.

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
13105 2022.09.19
2022.09.19
1 2 1 S17W71 0010 AXX AXX

location: S18W68

13106 2022.09.19
2022.09.20
      S12W88          

location: S11W83

13107 2022.09.20
2022.09.21
7 14 6 S24W53 0100 CAI CAI

location: S24W56

13110 2022.09.22
2022.09.23
1 1 1 N16W24 0170 HSX HSX

location: N16W23

S7891 2022.09.25       S12W57            
13111 2022.09.26
2022.09.27
1 13 4 N27E30 0100 HSX CSO

location: N27E31

S7893 2022.09.28   2   S15W09 0003   BXO  
S7894 2022.09.29       N12E15            
S7895 2022.09.29       N15W26          
13113 2022.09.29
2022.09.30
3 28 12 N16W14 0090 CAO DAI area: 0180
S7897 2022.09.29   2 1 N31E10 0004   AXX  
S7898 2022.09.30   8 4 S33E38 0020   CRI    
13112 2022.09.30
2022.09.30
1 1 1 N20E76 0100 HSX HSX   area: 0180

location: N19E77

was AR S7899

S7900 2022.09.30   3 1 S26W11 0006   BXO    
S7901 2022.09.30   7 5 N22E82 0350   DKC   beta-delta
S7902 2022.09.30   1   N28E82 0003   AXX    
S7903 2022.09.30   2   S12E35 0002   AXX    
Total spot count: 14 84 36  
Sunspot number: 74 214 136  (total spot count + 10 * number of spotted regions)
Weighted SN: 39 122 74  (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): 81 118 109  

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
2022.09 135.1 (1)   82.9 (2A/2B) / 108.4 (2C) (104.9 projected, +4.9) (12.2)
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.