Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 26, 2023 at 04:45 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 unsettled on January 25, weakly under the influence of effects from CH1126 during the latter half of the day. Solar wind speed at SOHO ranged between 375 and 468 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 171.8 - increasing 9.0 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 130.47). The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 5.6). Three hour interval K indices: 00123211 (planetary), 00133222 (Boulder), 00003313 (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 14 active regions using 2K resolution (SN: 260) and in 12 active regions using 1K resolution (SN: 177) SDO/HMI images.

Region 13190 [S14W83] rotated partly out of view and was the source of the largest flare of the day, an M4.6 event at 10:11.
Region 13192 [N17W84] became more unstable as it rotated mostly out of view and produced a number of C and M flares.
Region 13196 [N11W49] developed slowly and produced a few C flares.
Region 13197 [N17W43] was quiet and stable.
Region 13198 [N25W22] decayed slowly and quietly.
Region 13200 [N22E21] developed significantly gaining spots and area. The region has polarity intermixing. C flares and maybe even a minor M class flare is possible.
Region 13201 [N23E45] was quiet and stable.
New region 13203 [N17E31] emerged on January 24 and was numbered the next day by SWPC.

Spotted regions not observed (or interpreted differently) by SWPC:
S8195 [N10W07] decayed slowly and quietly.
S8196 [N17W07] has a weak magnetic delta and could produce C flares. Note that SWPC considers this and AR S8195 as one region.
S8200 [N21W33] was quiet and stable.
S8209 [S30E29] reemerged with tiny spots.
S8210 [N24E06] developed slowly and quietly.
New region S8213 [S27W00] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C3.6 01:38 northwest limb 13192? GOES16  
C4.2 01:49   13192 GOES16  
C3.7 01:54   13190 GOES16  
C4.9 02:55   13190 GOES16 simultaneous flare in AR S8194 behind the SW limb
C4.6 03:45   S8194 GOES16  
C4.5 04:00   13190 GOES16  
C9.6/1F 04:53 N14W74 13192 GOES16  
C4.8 05:54   13190 GOES16  
C6.5 06:08   13192 GOES16  
C4.7 06:30   13192 GOES16  
C5.8 08:04   13192 GOES16  
C7.2 08:27   13190 GOES16  
M4.6 10:11   13190 GOES16 LDE. Simultaneous smaller flare in AR 13192
C4.2 13:47   13192 GOES16  
C6.1 14:54   13192 GOES16  
C5.3 15:12   13190 GOES16  
C4.2 16:04   13190 GOES16  
C5.5 16:28   13190 GOES16  
M1.3 17:01 N17W77 13190 GOES16 simultaneous flare in AR 13192
C4.8 18:35   13190 GOES16  
C4.8 19:36 (peak likely earlier)   13190 GOES16  
C3.8 21:48   13192 GOES16  
C4.8 21:57 N19W75 13192 GOES16  
M2.0 22:35   13192 GOES16  

Coronal mass ejections (CMEs)

January 23-25: 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 unsettled geomagnetic conditions are expected on January 26 due to weak effects from CH1126. Effects from CH1127 could cause quiet to unsettled conditions on January 27-28.

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
13192 2023.01.12
2023.01.13
3 1   N15W84 0070 CAO HSX

location: N17W84

13190 2023.01.12
2023.01.13
3 4 3 S14W89 0680 DKC HKX

area: 1020

location: S14W83

S8185 2023.01.16       S13W46            
13196 2023.01.17
2023.01.18
8 15 7 N19W41 0060 CSO DRI

location: N11W49

SWPC data is very confusing. They have moved AR 13196 to near the location of AR 13197 and created new AR 13202 in the location of AR 13196. Meanwhile the SWPC guys analysing flares are still using the old, correct position of AR 13196

13198 2023.01.18
2023.01.19
1 4 3 N25W24 0070 HSX HAX

location: N25W22

13197 2023.01.18
2023.01.19
3 9 4 N20W32 0030 CRO CAO location: N17W43

AR 13197 is another victim in the confusion SWPC has created with their January 25 interpretation. The region has been moved to near the location of AR S8200 as the original AR 13196 has been moved to the location of AR 13197.

S8193 2023.01.18       N27W51            
S8195 2023.01.19   4 2 N10W07 0010   BXO  
S8196 2023.01.19   15 7 N17W07 0040   DRI beta-delta
S8198 2023.01.19       S14W48            
S8199 2023.01.19       S49W52            
S8200 2023.01.19   11 4 N21W33 0040   DRO  
13199 2023.01.20 6     N18W08 0040 CAO       SWPC considers ARs S8195 and S8196 to be one group
13200 2023.01.21
2023.01.22
7 32 16 N21E22 0050 CAO DRI

beta-gamma

location: N22E21

area: 0090

S8203 2023.01.21       S24W34            
S8204 2023.01.21       N13E29            
S8205 2023.01.21       N17W35          
S8206 2023.01.21       S30W30            
S8207 2023.01.22       N01W41            
13201 2023.01.23
2023.01.24
1 1 1 N24E44 0070 HSX HSX area: 0100

location: N23E45

S8209 2023.01.23   3   S30E29 0004   BXO    
S8210 2023.01.23   7 3 N24E06 0020   CRO  
S8211 2023.01.24       S04W20          
13203 2023.01.24
2023.01.25
3 13 6 N16E32 0010 BXO CRI area: 0040
13202 2023.01.25 5     N13W47 0010 CAO       SWPC has created a new region in the position of old AR 13196
S8213 2023.01.25   1 1 S27W00 0004   AXX    
Total spot count: 40 120 57  
Sunspot number: 140 260 177  (total spot count + 10 * number of spotted regions)
Weighted SN: 88 168 105  (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): 154 143 142  

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
2023.01 192.4 (1)   118.1 (2A) / 146.5 (2B) / 173.7 (2C) (113.1 projected, +6.0) (9.0)
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.