Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 19, 2023 at 05:00 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 (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 (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 January 18 due to CME effects.Solar wind speed at SOHO ranged between 346 and 600 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 220.3 - increasing 89.0 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 128.60). The Potsdam WDC planetary A index was 14 (STAR Ap - based on the mean of three hour interval ap indices: 14.4). Three hour interval K indices: 44332220 (planetary), 33333331 (Boulder), 55222312 (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: 401) and in 12 active regions using 1K resolution (SN: 258) SDO/HMI images.

Region 13184 [S13W51] was quiet and stable.
Region 13186 [N22W43] was mostly quiet and stable.
Region 13188 [S25W17] decayed slowly and quietly.
Region 13190 [S14E07] produced the largest flare of the day and has major flare potential. No major changes were observed.
Region 13191 [N11W02] was mostly quiet and stable.
Region 13192 [N18E10] was mostly unchanged and produced a few flares. M class flares are possible. C1 flare: C1.9 @ 18:15 UT.
Region 13193 [S22W68] decayed slowly and quietly.
Region 13194 [S23W02] decayed slowly and quietly.
Region 13195 [N21W10] decayed slowly and quietly.
New region 13196 [N12E45] emerged on January 17 and was numbered by SWPC the next day. A magnetic delta has formed in the trailing spot section and further C and M class flaring is likely. The region was the source of an M1.1 flare at 04:03 UT on January 19.

Spotted regions not observed (or interpreted differently) by SWPC:
S8178 [N12E11] developed slowly and was mostly quiet.
New region S8190 [N27E69] rotated into view with small spots.
New region S8192 [N17E58] emerged with tiny spots.
New region S8193 [N23E47] emerged with tiny spots.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C3.0 01:21   13186 GOES16  
C4.1 01:42   13196 GOES16  
C2.3 02:42   S8178 GOES16  
C2.9 03:25   13190 GOES16  
C3.7 03:58   S8178 GOES16  
C5.0 05:13   13192 GOES16  
C7.9 05:19 S17E26 13190 GOES16 simultaneous flare in AR S8178
C2.3 06:39   S8178 GOES16  
C2.6 06:50   13196 GOES16  
C2.3 09:43   S8178 GOES16  
M1.8 10:35   13190 GOES16  
C2.4 13:13   13190 GOES16  
C2.2 13:25   13192 GOES16  
C3.3 14:07   13196 GOES16  
C5.9 14:40   13196 GOES16 incorrectly attributed to AR 13186 by SWPC
C3.4 15:31 N19E17 13192 GOES16  
C2.8 16:01   13190 GOES16  
C9.4 20:47   13192 GOES16  
C2.5 21:35   S8178 GOES16  
C2.2 22:26   13192 GOES16  
C3.6 23:06 S21E16 13190 GOES16  

Coronal mass ejections (CMEs)

January 16-18: 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 small and poorly defined trans equatorial coronal hole (CH1125) was Earth facing on January 16. A southern hemisphere coronal hole (CH1126) will likely rotate across the central meridian on January 21.

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 unsettled geomagnetic conditions are likely on January 19-21 with a chance of active intervals on January 19-20 if a high speed stream from CH1125 arrives.

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
3 18 4 S13W51 0180 CSO CSO

 

13186 2023.01.09
2023.01.10
5 16 7 N24W41 0350 EHO EHO

location N23W43

area: 0460

13188 2023.01.10
2023.01.12
3 6   S24W16 0010 BXO BXO location: S25W17
13191 2023.01.12
2023.01.13
8 21 17 N11W04 0230 DSI DSI

location: N11W02

13192 2023.01.12
2023.01.13
17 59 32 N16E13 0420 FKI FAI beta-gamma-delta

location: N18E10

13190 2023.01.12
2023.01.13
17 50 38 S15E09 0950 EKI EKI beta-gamma

area: 1070

location: S14E07

13195 2023.01.13
2023.01.17
5 14 5 N20W09 0030 CRO DRO location: N21W10
S8178 2023.01.13   30 15 N12E11 0080   DRI  
13194 2023.01.13
2023.01.15
2 15 6 S23W04 0000 BXO BXO

location: S23W02

area: 0030

S8180 2023.01.13       S18W45            
S8181 2023.01.13       S22W09            
13193 2023.01.14
2023.01.15
2 5 3 S22W70 0010 BXO BXO

location: S22W68

S8184 2023.01.14       S27W41            
S8185 2023.01.16       S13E45            
S8186 2023.01.17       S27E11          
13196 2023.01.17
2023.01.18
2 14 7 N12E44 0030 DRO DRI beta-delta

area: 0060

S8190 2023.01.18   5 2 N27E69 0030   CRO    
S8192 2023.01.18   5 2 N17E58 0010   BXO    
S8193 2023.01.18   3   N23E47 0004   BXO    
Total spot count: 64 261 138  
Sunspot number: 164 401 258  (total spot count + 10 * number of spotted regions)
Weighted SN: 110 308 185  (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): 180 221 206  

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) 11.2
2023.01 190.0 (1)   81.5 (2A) / 140.4 (2B) / 156.1 (2C) (113.1 projected, +6.0) (9.6)
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.