Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 17, 2023 at 11:30 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 16 due to weakening CME effects. Solar wind speed at SOHO ranged between 444 and 540 km/sec. The high latitude magnetometer at Andenes recorded quiet to active levels.

Solar flux density measured at 20h UT on 2.8 GHz was 228.1 - increasing 81.7 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 128.03). 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: 42333311 (planetary), 31344211 (Boulder), 32333433 (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 12 active regions using 2K resolution (SN: 380) and in 11 active regions using 1K resolution (SN: 244) SDO/HMI images.

Region 13182 [S15W74] decayed further and produced the largest flare of the day.
Region 13184 [S13W25] decayed slowly and quietly.
Region 13186 [N23W16] decayed slowly and quietly.
Region 13188 [S23E08] decayed slowly and quietly.
Region 13190 [S14E33] has a huge leader spot and major flare potential. Minor magnetic delta configurations was observed at the southern edge of the leading penumbra and in small trailing penumbrae.
Region 13191 [N10E25] decayed slowly and was mostly quiet.
Region 13192 [N18E36] was mostly quiet and stable. A major flare is possible.
Region 13193 [S22W43] decayed slowly and quietly.
Region 13194 [S23E24] decayed slowly and quietly.

Spotted regions not observed (or interpreted differently) by SWPC:
S8177 [N20E18] developed slowly and produced several C flares.
S8178 [N10E39] gained tiny spots and was quiet.
New region S8185 [S13E71] emerged with tiny spots.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.7 01:45   13191 GOES16  
C4.0 02:37   13182 GOES16  
C3.0 03:50   13192 GOES16  
C4.6 04:42 S14E48 13190 GOES16  
C5.0 05:18   13182 GOES16 incorrectly attributed to AR 13191 by SWPC
C2.6 07:30   13182 GOES16  
C8.7/1N 09:23 S16W69 13182 GOES16  
C3.1 11:44   S8177 GOES16  
C4.4 11:49   S8177 GOES16  
C2.6 13:52   S8177 GOES16  
C3.6 14:31   S8177 GOES16  
C3.1 14:58   S8177 GOES16  
C2.8 16:02   13190 GOES16  
C2.8 17:43   S8177 GOES16  
C2.5 21:36   13190 GOES16  
C2.3 22:41   13182 GOES16  

Coronal mass ejections (CMEs)

January 15-16: No obviously Earth directed CMEs were observed in available LASCO imagery.
January 14: A partial halo CME was observed after an M3.6 flare in AR 13182 at 21:00 UT. The CME could reach Earth on January 17 or 18 and cause unsettled to minor storm conditions.

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.

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 is expected on January 17-18 due to CME effects (from January 14 CME) becoming quiet to unsettled on January 19-20 with a chance of active intervals 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
13182 2023.01.04
2023.01.05
5 12 5 S17W75 0020 CRO CRO

location: S16W61

area: 0030

13184 2023.01.08
2023.01.08
7 26 14 S13W24 0210 CSO CSO

 

13187 2023.01.09
2023.01.10
      N16W66           location: N14W61
13186 2023.01.09
2023.01.10
14 35 15 N25W15 0440 EHO EKO

location N23W16

area: 0660

13188 2023.01.10
2023.01.12
10 17 10 S24E09 0030 DRO DRO location: S23E08

area: 0050

13189 2023.01.11
2023.01.13
      N23W73         location: N19W70
S8170 2023.01.12       N19E10           reversed polarities
13191 2023.01.12
2023.01.13
13 29 16 N12E22 0360 DKC DAO

location: N10E25

13192 2023.01.12
2023.01.13
13 36 18 N19E40 0400 FKI FAI beta-gamma

location: N18E36

13190 2023.01.12
2023.01.13
21 45 28 S14E34 0880 EHI EKO beta-gamma-delta

location: S14E33

area: 1270

S8177 2023.01.13   20 11 N20E18 0060   DRI  
S8178 2023.01.13   14 6 N10E39 0020   BXO  
13194 2023.01.13
2023.01.15
7 13 5 S23E23 0010 BXO BXO

location: S23E24

S8180 2023.01.13       S18W19            
S8181 2023.01.13       S22E17          
13193 2023.01.14
2023.01.15
6 11 6 S22W43 0060 DSO DAO

 

S8184 2023.01.14       S27W15            
S8185 2023.01.16   2   S13E71 0002   AXX    
Total spot count: 96 260 134  
Sunspot number: 186 380 244  (total spot count + 10 * number of spotted regions)
Weighted SN: 152 309 183  (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): 205 209 195  

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
2023.01 186.1 (1)   70.3 (2A) / 136.2 (2B) / 150.7 (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.