Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 25, 2023 at 04:50 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 (January 6, 2023)
Solar cycle Solar cycles 23-25 (January 1, 2023) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (January 1, 2023) 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 (January 1, 2023) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (January 1, 2023) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (January 21, 2023) 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 on January 24. Solar wind speed at SOHO ranged between 374 and 461 km/sec. The high latitude magnetometer at Andenes recorded quiet to unsettled levels.

Solar flux density measured at 20h UT on 2.8 GHz was 180.2 - increasing 19.8 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 130.28). The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 3.8). Three hour interval K indices: 11121110 (planetary), 11122321 (Boulder), 31111000 (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: 260) and in 14 active regions using 1K resolution (SN: 208) SDO/HMI images.

Region 13190 [S14W73] decayed in the leading spot section. A major flare is possible.
Region 13192 [N17W71] produced a few flares with no significant development observed.
Region 13196 [N12W35] decayed slowly and quietly.
Region 13197 [N18W30] was quiet and stable.
Region 13198 [N26W09] decayed slowly and quietly.
Region 13200 [N22E35] was quiet and stable.
New region 13201 [N24E58] rotated into view on January 23 with SWPC numbering the region the next day.

Spotted regions not observed (or interpreted differently) by SWPC:
S8194 [S24W80] decayed losing spots and area.
S8195 [N12E05] was quiet and stable.
S8196 [N18E20] has a weak magnetic delta and could produce C flares. Note that SWPC considers this and AR S8195 as one region.
S8200 [N22W22] was quiet and stable.
S8205 [N17W22] was quiet and stable.
S8210 [N24E19] decayed slowly and quietly during the latter half of the day.
New region S8211 [S04W07] emerged with a tiny spot.
New region S8212 [N18E44] emerged with tiny spots.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.4 02:19   13190 GOES16  
C2.7 02:55   S8194 GOES16  
C6.6 04:26   S8194 GOES16  
C4.0 05:47 S24W68 S8194 GOES16 simultaneous flare in AR 13190
C2.4 07:07 N12W62 13191 GOES16  
C2.7 08:30 NW quadrant   GOES16 filament eruption
C2.3 10:43   13190 GOES16  
C2.5 13:22 N15W66 13192 GOES16  
C3.7 13:42   13192 GOES16  
C9.4 14:35 N19W62 13192 GOES16 LDE, filament eruption
C8.6 15:15   13192 GOES16  
C3.2 16:49   13190 GOES16  
C2.1 19:42   13192 GOES16  
C2.5 20:23   13192 GOES16  
C3.0 22:50   13190 GOES16  
C4.5 23:45   13192 GOES16  

Coronal mass ejections (CMEs)

January 22-24: No obviously Earth directed CMEs were observed in available LASCO imagery.

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 trans equatorial coronal hole (CH1126) rotated across the central meridian on January 21-22. A northern hemisphere coronal hole (CH1127) was Earth facing on January 24. A recurrent southern hemisphere coronal hole (CH1128) could become Earth facing on January 28.

Propagation

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

Forecast

Quiet to active geomagnetic conditions are expected on January 25-26 due to effects from CH1126. Quiet to unsettled is likely on January 27.

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
13191 2023.01.12
2023.01.13
      N10W85        

 

13192 2023.01.12
2023.01.13
4 14 11 N16W70 0130 CAO CAO

location: N17W71

13190 2023.01.12
2023.01.13
6 15 10 S14W78 0880 DKC EKC beta-gamma-delta

area: 1060

location: S14W73

13194 2023.01.13
2023.01.15
4     S24W84 0120 DAO      

merged with AR S8194

S8185 2023.01.16       S13W33            
13196 2023.01.17
2023.01.18
2 8 4 N15W34 0010 CSO BXO

location: N12W35

13198 2023.01.18
2023.01.19
1 6 2 N26W10 0060 CSO CAO

location: N26W09

13197 2023.01.18
2023.01.19
5 9 5 N20W24 0060 DAO CAO location: N18W30
S8193 2023.01.18       N27W38            
S8194 2023.01.19   8 5 S24W80 0040   DRO  
S8195 2023.01.19   2 2 N12E05 0008   BXO  
S8196 2023.01.19   17 12 N18E07 0060   DRI beta-delta
S8198 2023.01.19       S14W35            
S8199 2023.01.19       S49W39            
S8200 2023.01.19   7 4 N22W22 0070   DRO  
13199 2023.01.20 12     N16E05 0060 CAO       SWPC considers ARs S8195 and S8196 to be one group
13200 2023.01.21
2023.01.22
2 10 6 N23E35 0040 CAO CAO

location: N22E35

area: 0060

S8203 2023.01.21       S24W21            
S8204 2023.01.21       N13E42            
S8205 2023.01.21   4 2 N17W22 0020   BXO  
S8206 2023.01.21       S30W17            
S8207 2023.01.22       N01W28            
13201 2023.01.23
2023.01.24
1 2 1 N25E58 0020 HSX HSX area: 0090

location: N24E58

S8209 2023.01.23       S29E41          
S8210 2023.01.23   2 2 N24E19 0007   BXO  
S8211 2023.01.24   1   S04W07 0002   AXX    
S8212 2023.01.24   5 2 N18E44 0012   BXO    
Total spot count: 37 110 68  
Sunspot number: 127 260 208  (total spot count + 10 * number of spotted regions)
Weighted SN: 87 154 112  (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): 140 143 166  

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
2021.06 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 64.7 (+4.6) 10.46
2022.03 117.0 115.8 78.6 68.7 (+4.0) 10.20
2022.04 130.8 131.7 84.0 73.0 (+4.3) 11.79
2022.05 133.8 136.8 96.5 77.2 (+4.2) 7.48
2022.06 116.1 119.8 70.3 80.9 (+3.7) 8.20
2022.07 125.4 129.5 91.4 (86.0 projected, +5.1) 9.51
2022.08 114.2 117.1 74.6 (91.4 projected, +5.4) 10.92
2022.09 135.1 136.5 96.0 (96.3 projected, +4.9) 12.18
2022.10 133.5 132.7 95.4 (99.5 projected, +3.2) 11.16
2022.11 123.4 120.7 77.6 (102.3 projected, +2.8) 9.33
2022.12 147.9 143.4 113.1 (107.1 projected, +4.8) 11.13
2023.01 193.3 (1)   113.6 (2A) / 146.8 (2B) / 172.7 (2C) (113.1 projected, +6.0) (9.2)
2023.02       (118.2 projected, +5.1)  
2023.03       (121.3 projected, +3.1)  
2023.04       (126.7 projected, +5.4)  
2023.05       (132.5 projected, +5.8)  
2023.06       (135.7 projected, +3.2)  
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.