Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 9, 2023 at 06:40 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 unsettled on January 8. Solar wind speed at SOHO ranged between 356 and 461 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 183.8 - increasing 33.0 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 125.83). The Potsdam WDC planetary A index was 8 (STAR Ap - based on the mean of three hour interval ap indices: 7.5). Three hour interval K indices: 22223110 (planetary), 2222430x (Boulder), 33212211 (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 11 active regions using 2K resolution (SN: 331) and in 10 active regions using 1K resolution (SN: 213) SDO/HMI images.

Region 13177 [S18W71] decayed slowly and quietly.
Region 13181 [S16W21] developed in the northern part while decay was observed in the southern part.
Region 13182 [S16E32] decayed slightly in the southern spot section and became less active after noon. The region still has weak magnetic deltas and could produce a major flare.
Region 13183 [S17W50] decayed slowly and quietly.
New region 13184 [S13E80] rotated into view and was very active all day. Further M class flaring is likely, and a major flare is possible.

Spotted regions not observed (or interpreted differently) by SWPC:
S8133 [N17W51] decayed slowly and quietly
S8135 [N21W47] decayed slowly and quietly.
S8155 [S21W15] still has small magnetic deltas in the northern and western part of the trailing penumbra. Some loss of area was observed. The region has been mostly quiet, however, an M class flare is possible.
S8159 [N20E15] developed slowly and quietly.
New region S8161 [S15E12] was observed with tiny spots in an old plage area.
New region S8162 [S31E17] was observed with tiny spots in an old plage area.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C4.3 02:29 S16E38 13182 GOES16  
C6.3/1F 03:08   13182 GOES16  
C7.0 03:31   13182 GOES16  
C9.3 03:44   13182 GOES16  
C8.0 04:55   13184 GOES16  
C7.0 05:47   13184 GOES16  
C5.7 06:07   13182 GOES16  
C5.0 07:05   13182 GOES16  
C6.3 07:24   13182 GOES16 simultaneous flare in AR 13184
C5.7 07:48   13184 GOES16  
M1.2 08:54   13184 GOES16  
M1.4 09:48   13184 GOES16  
C8.0 10:29 northwest limb S8158? GOES16  
C4.4 11:14   13184 GOES16  
C5.3 12:05 S17E40 13182 GOES16  
C6.1 12:38   13184 GOES16  
C6.0 12:50   13184 GOES16  
C5.4 14:36   13184 GOES16  
M1.4 15:07   13184 GOES16  
C2.6 16:00   13184 GOES16  
C2.2 17:10   13184 GOES16  
C9.7 18:57   13184 GOES16  
M1.0 19:11 S15E86 13184 GOES16  
C2.6 21:09 northwest limb S8158? GOES16  
C3.1 21:41   13182 GOES16  
C2.0 22:44   13184 GOES16  

Coronal mass ejections (CMEs)

January 6-8: 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 poor to fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

Mostly quiet geomagnetic conditions are expected on January 9-11 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
13177 2022.12.27
2022.12.28
1 4 2 S18W72 0010 AXX BXO  
S8133 2022.12.29   1 1 N17W51 0100   HSX  
13180 2022.12.30 3     N18W50 0090 CSO       SWPC consider AR S8133 and S8135 to be one region
S8135 2022.12.30   6 2 N21W47 0060   CAO  
13181 2022.12.31
2023.01.01
19 43 22 S20W20 0410 EKI DRI area: 0100

location: S16W21

SWPC considers this and AR S8155 as one region

S8146 2023.01.02       S13W40            
S8149 2023.01.03       N33W50            
S8150 2023.01.03       N14W33            
13183 2023.01.03
2023.01.05
8 25 16 S17W49 0180 DAO EAI  
S8153 2023.01.04       S10W26            
13182 2023.01.04
2023.01.05
23 84 36 S17E32 0880 EKI EKI beta-gamma-delta

location: S16E32

S8155 2023.01.05   35 25 S21W15 0500   DKC beta-delta
S8157 2023.01.05       S02E01            
S8159 2023.01.06   10 4 N20E15 0020   BXO  
13184 2023.01.08
2023.01.08
3 7 4 S13E81 0240 HAX DKC   beta-delta?

area: 0400

S8161 2023.01.08   4 1 S15E12 0008   AXX    
S8162 2023.01.08   2   S31E17 0005   AXX    
Total spot count: 57 221 113  
Sunspot number: 117 331 213  (total spot count + 10 * number of spotted regions)
Weighted SN: 92 269 151  (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): 129 182 170  

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
2023.01 161.0 (1)   25.4 (2A) / 98.5 (2B) / 138.1 (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.