Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 10, 2023 at 07:10 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 (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 on January 9. Solar wind speed at SOHO ranged between 314 and 398 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 190.9 - increasing 37.9 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 126.06). The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 4.1). Three hour interval K indices: 20011122 (planetary), 21121232 (Boulder), 31000333 (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: 369) and in 10 active regions using 1K resolution (SN: 229) SDO/HMI images.

Region 13181 [S16W34] developed further and gained a magnetic delta.
Region 13182 [S17E19] has several minor magnetic delta and could produce a major flare. Significant decay was observed in the trailing spot sections.
Region 13183 [S17W65] decayed slowly and quietly.
Region 13184 [S13E68] is a compact region with a complex magnetic layout in the leading spot section. A fairly long neutral line and positive polarity flux sandwiched between negative polarity flux areas in the trailing part of the leading spot section, probably contributed to the major X1 flare. Further M and X class flaring is likely.
New region 13185 [N19E01] was first observed with spots on January 6 and was numbered 3 days later by SWPC when new flux emerged.

Spotted regions not observed (or interpreted differently) by SWPC:
S8133 [N17W64] decayed slowly and quietly
S8135 [N21W60] decayed losing mature penumbra.
S8155 [S22W29] decayed slowly and was mostly quiet.
S8161 [S17W02] was quiet and stable.
New region S8163 [N13E31] emerged with several spots late in the day.
New region S8164 [N23E78] rotated into view with a few small spots. The region is very unstable and was the source of a major M5.1 flare at 00:16 UT on January 10.
New region S8165 [S07E15] was observed with tiny spots.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C5.1 00:43 S21E39 13182 GOES16  
M1.1 01:02   13184 GOES16  
C4.3/1N 02:00   13181 GOES16  
C5.7 02:07   13184 GOES16  
C4.8 04:51 S16E82 13184 GOES16  
C3.0 05:52   13184 GOES16  
C2.6 06:18   13184 GOES16  
C2.9 07:05 S16E82 13184 GOES16  
C2.8 07:31   13184 GOES16  
M2.1/1N 09:01   13181 GOES16 simultaneous flare in AR 13184
C5.1 10:04   13181 GOES16  
C4.3 10:37   13184 GOES16  
C3.0 11:32   13181 GOES16  
C2.6 12:29   13181 GOES16  
M1.0 13:22   13181 GOES16  
C2.8 14:20   13184 GOES16  
C7.8/1F 15:05 S15E74 13184 GOES16  
C5.1 15:46   13184 GOES16  
C4.1 16:08   13184 GOES16  
C4.6 16:48 S16W29 13181 GOES16  
C3.0 17:21   13184 GOES16  
C3.0 17:48   13184 GOES16 simultaneous flare in AR S8164
C2.6 17:57   13184 GOES16  
X1.9/3B 18:50 S14E72 13184 GOES16 much smaller simultaneous flare in AR S8164
C5.9 20:55 N24E79 S8164 GOES16  
C3.0 21:18   13184 GOES16  
C4.1 22:09 N24E80 S8164 GOES16  
C4.3 22:34   S8164 GOES16  
C6.7 22:58 S17E23 S8155 GOES16  

Coronal mass ejections (CMEs)

January 7-9: 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 northern hemisphere coronal hole (CH1124) may have been too far to the north to cause geomagnetic effects. CH1124 rotated across the central meridian on January 7.

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

Mostly quiet geomagnetic conditions are expected on January 10-12 with a chance of unsettled and active intervals on January 10-11 should effects from CH1124 reach Earth.

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
S8133 2022.12.29   2 1 N17W64 0090   CSO  
13180 2022.12.30 3     N18W63 0100 HSX       SWPC considers AR S8133 and S8135 to be one region
S8135 2022.12.30   3 2 N21W60 0020   HRX  
13181 2022.12.31
2023.01.01
35 34 19 S19W33 0700 EKC DAC area: 0200

beta-gamma-delta

location: S16W34

SWPC considers this and AR S8155 as one region

S8146 2023.01.02       S13W53            
S8150 2023.01.03       N14W46            
13183 2023.01.03
2023.01.05
6 11 3 S17W62 0110 CSO CAO area: 0090

location: S17W65

S8153 2023.01.04       S10W39            
13182 2023.01.04
2023.01.05
30 102 51 S17E20 0950 EKC FKI beta-gamma-delta

location: S17E19

S8155 2023.01.05   38 23 S22W29 0690   DKC  
S8157 2023.01.05       S02W12            
13185 2023.01.06
2023.01.09
4 19 11 N20W00 0030 CRO CRO area: 0050

location: N19E01

13184 2023.01.08
2023.01.08
4 17 13 S14E67 0400 HKX FKC beta-gamma-delta

area: 0470

S8161 2023.01.08   5   S17W02 0010   AXX  
S8162 2023.01.08       S31E04          
S8163 2023.01.09   7 3 N13E31 0025   DRO    
S8164 2023.01.09   7 3 N23E78 0050   DRI    
S8165 2023.01.09   4   S07E15 0008   BXO    
Total spot count: 82 249 129  
Sunspot number: 142 369 229  (total spot count + 10 * number of spotted regions)
Weighted SN: 125 306 186  (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): 156 203 183  

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
2023.01 164.3 (1)   30.0 (2A) / 103.3 (2B) / 138.7 (2C) (113.1 projected, +6.0) (8.6)
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.