Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 22, 2023 at 10:10 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 to active on January 21, likely under the influence of effects from CH1125. Solar wind speed at SOHO ranged between 409 and 532 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 208.7 - increasing 64.7 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 129.53). The Potsdam WDC planetary A index was 16 (STAR Ap - based on the mean of three hour interval ap indices: 15.9). Three hour interval K indices: 34422333 (planetary), 23222441 (Boulder), 34423454 (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 19 active regions using 2K resolution (SN: 440) and in 15 active regions using 1K resolution (SN: 278) SDO/HMI images.

Region 13184 [S14W79] rotated mostly out of view with only a tiny trailing spot visible by the end of the day.
Region 13190 [S14W33] developed a magnetic delta in the northern part of the huge penumbra. A major flare is possible.
Region 13191 [N11W43] decayed and lost penumbra on the trailing spots.
Region 13192 [N18W31] decayed slowly producing a few C flares.
Region 13195 [N21W50] decayed slowly and quietly.
Region 13196 [N11E05] decayed slowly and quietly.
Region 13197 [N18E17] developed slowly and quietly.
Region 13198 [N25E29] was quiet and stable.

Spotted regions not observed (or interpreted differently) by SWPC:
S8178 [N12W28] decayed slowly and quietly.
S8193 [N28E03] was quiet and stable.
S8194 [S24W47] developed further and merged with AR 13194. The region has magnetic deltas and could produce C and minor M class flares.
S8195 [N11E47] was quiet and stable.
S8196 [N17E48] developed slowly and quietly. Note that SWPC considers this and AR S8195 as one region.
S8200 [N23E20] was quiet and stable.
New region S8202 [N22E75] rotated into view with a mature spot.
New region S8203 [S24E18] emerged with tiny spots.
New region S8204 [N13E81] rotated into view with a tiny spot.
New region S8205 [N14E18] emerged with tiny spots and with reversed polarities.
New region S8206 [S30E12] emerged with tiny spots.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.9 01:52   13192 GOES16  
C2.5 02:20   13184 GOES16  
C3.0 02:38   13184 GOES16  
C3.2 04:03   13184 GOES16  
C2.2 04:43   13184 GOES16  
C4.5 05:38   13184 GOES16  
C2.8 06:33   S8186 GOES16  
C3.2 09:22   13190 GOES16  
C4.6 09:44   S8196 GOES16  
C3.6 11:10   13186 GOES16  
C3.7 11:25 N17W20 13192 GOES16 simultaneous flare in AR 13184
C3.0 11:49   13184 GOES16 simultaneous flare in AR 13190
C3.7 12:47   S8196 GOES16  
C3.4 13:50   13192 GOES16  
C3.1 15:04   13190 GOES16  
C5.0 16:41 N22W17 13192 GOES16  
C3.2 18:31   13192 GOES16  
C5.6 20:18 S27W43 S8194 GOES16  
C2.2 22:54   S8202 GOES16  
C2.3 23:43   13194 GOES16  

Coronal mass ejections (CMEs)

January 19: No obviously Earth directed CMEs were observed in available LASCO imagery.
January 20: A large filament eruption began near noon in the southwest quadrant and apparently triggered a C5 flare in AR 13190 at 14:07 UT. A partial halo CME was observed in LASCO imagery. There is a slight chance of CME effects at Earth on January 24.

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 small and poorly defined trans equatorial coronal hole (CH1125) was Earth facing on January 16. A southern hemisphere coronal hole (CH1126) will rotate across the central meridian on January 21-22.

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 to fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

Quiet to unsettled geomagnetic conditions are expected for January 22-25 with a chance of active and minor storm intervals on January 24 should the January 20 CME arrive.

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
13184 2023.01.08
2023.01.08
1 1 1 S12W93 0020 HSX AXX

location: S14W79

area: 0003

13186 2023.01.09
2023.01.10
1     N24W81 0060 HSX     rotated out of view
13188 2023.01.10
2023.01.12
      S23W51         location: S23W55
13191 2023.01.12
2023.01.13
6 14 8 N12W44 0140| DAO CAO

location: N11W43

area: 0090

13192 2023.01.12
2023.01.13
29 37 19 N16W29 0270 FKI CAI

location: N18W31

13190 2023.01.12
2023.01.13
17 58 33 S15W31 0670 EKI DKC beta-gamma-delta

area: 1010

location: S14W33

13195 2023.01.13
2023.01.17
  1   N21W50 0001   BXO  
S8178 2023.01.13   18 7 N12W28 0030   BXO  
13194 2023.01.13
2023.01.15
15     S25W44 0080 CAO      

location: S22W40

spotless, see AR S8194

S8185 2023.01.16       S13E06            
S8186 2023.01.17       S27W28            
13196 2023.01.17
2023.01.18
1 8 4 N12E02 0010 AXX BXO

area: 0015

13198 2023.01.18
2023.01.19
6 12 4 N27E31 0030 CSO CAO area: 0100

location: N25E29

13197 2023.01.18
2023.01.19
8 21 15 N24E18 0010 CRO DRO location: N18E17

SWPC position is way off

area: 0050

S8193 2023.01.18   2   N28E03 0005   BXO  
S8194 2023.01.19   37 19 S24W32 0140   DRI beta-gamma-delta
S8195 2023.01.19   3 2 N11E47 0020   HRX  
S8196 2023.01.19   29 11 N17E48 0110   DRI  
S8197 2023.01.19       S11W38            
S8198 2023.01.19       S14E04          
S8199 2023.01.19       S49W00            
S8200 2023.01.19   2 1 N23E20 0005   BXO  
13199 2023.01.20 10     N15E47 0090 DAI       SWPC considers ARs S8195 and S8196 to be one group
S8202 2023.01.21   1 1 N22E75 0090   HAX    
S8203 2023.01.21   1 1 S24E18 0005   AXX    
S8204 2023.01.21   1   N13E81 0002   AXX    
S8205 2023.01.21   2 2 N14E18 0005   BXO   reversed polarities
S8206 2023.01.21   2   S30E12 0004   BXO    
Total spot count: 94 250 128  
Sunspot number: 194 440 278  (total spot count + 10 * number of spotted regions)
Weighted SN: 137 292 172  (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): 217 242 222  

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
2023.01 193.9 (1)   99.5 (2A) / 146.9 (2B) / 170.0 (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.