Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 11, 2023 at 06:50 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 10 under the influence of weak coronal hole effects after noon. Solar wind speed at SOHO ranged between 322 and 420 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 193.0 - increasing 28.3 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 126.30). The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 6.1). Three hour interval K indices: 11112322 (planetary), 10112332 (Boulder), 31001335 (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 13 active regions using 2K resolution (SN: 420) and in 11 active regions using 1K resolution (SN: 273) SDO/HMI images.

Region 13181 [S15W47] lost the main magnetic delta but still has a weak delta in a northern penumbra. C and M class flares are possible.
Region 13182 [S17E05] decayed in the trailing spot sections and was mostly quiet.
Region 13183 [S17W78] decayed slowly and quietly.
Region 13184 [S13E53] decayed slowly with the magnetic delta weakening. M class flaring is still likely.
Region 13185 [N19W12] developed slowly. In the central spot section tiny opposite polarity spots are close to each other and may have been the cause of a C5 flare. The region is unimpressive but does have weak polarity intermixing.
New region 13186 [N23E63] rotated into view on January 9 and developed further on January 10 when it was numbered by SWPC. The leading penumbra has a strong magnetic delta with almost no separation between opposite polarity umbrae. Further M and X class flares are likely until the delta disappears.
New region 13187 [N13E18] emerged on January 9 with SWPC numbering the region the following day.

Spotted regions not observed (or interpreted differently) by SWPC:
S8133 [N17W78] decayed slowly and quietly.
S8135 [N21W73] decayed further with only tiny spots remaining by the end of the day.
S8155 [S23W41] decayed slowly and was mostly quiet. C and M flares are possible.
S8165 [S07W00] was quiet and stable.
New region S8167 [S17W57] was split off from AR 13181 as a bipolar region formed.
New region S8168 [S24E82] rotated into view with small spots.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
M5.1 00:16 N23E80 13186 GOES16  
C6.3 00:51 N23E80 13186 GOES16  
M1.0 02:16 S16E75 13184 GOES16  
M2.6/2N 02:41 S16W26 13181 GOES16  
C5.4 03:43 N23E77 13186 GOES16  
C2.5 05:17 N23E77 13186 GOES16  
C3.8 05:59 S16E75 13184 GOES16  
C3.4 06:45   13182 GOES16  
C5.3 08:16   13184 GOES16 incorrectly attributed to AR 13186 by SWPC
C3.7 08:30   13186 GOES16  
C8.8 09:06   13186 GOES16  
C2.8 10:41   S8133 GOES16  
M1.0 11:08   13184 GOES16  
C4.6 11:26 southeast limb S8168 GOES16  
C8.5 12:17 southeast limb S8168 GOES16  
C3.7 12:37   13186 GOES16  
C5.3 12:45   13185 GOES16  
C5.1 13:02   13184 GOES16  
C6.8 13:59   13186 GOES16 simultaneous flare in AR 13186
C8.7 14:47   13184 GOES16  
C6.0 15:19   13186 GOES16  
C7.3 16:13   13186 GOES16  
M1.3 17:28   13186 GOES16  
M1.2 17:48   13184 GOES16  
C2.9 19:10   13181 GOES16  
C3.3 19:38   13182 GOES16  
C2.8 20:18   13184 GOES16  
C3.6 20:46   13186 GOES16 simultaneous flare in AR 13182
C2.2 21:34   13186 GOES16  
X1.0/2B 22:47   13186 GOES16  
C5.2 23:57   13186 GOES16 simultaneous flares in AR 13182 and 13181
uncertain which one contributed the most

Coronal mass ejections (CMEs)

January 8-10: 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) 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

Quiet to unsettled geomagnetic conditions are expected on January 11 due to weak effects from CH1124. Mostly quiet conditions are likely on January 12-13.

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   1 1 N17W78 0080   HSX  
13180 2022.12.30 1     N17W78 0050 HSX       SWPC considers AR S8133 and S8135 to be one region
S8135 2022.12.30   1   N21W73 0001   AXX  
13181 2022.12.31
2023.01.01
44 39 24 S17W47 0700 EKC DAI area: 0270

beta-gamma-delta

location: S15W47

SWPC considers this, ARs S8155 and S8167 as one region

13183 2023.01.03
2023.01.05
2 2 2 S16W77 0100 HAX HAX area: 0050

location: S17W78

S8153 2023.01.04       S10W52            
13182 2023.01.04
2023.01.05
51 119 61 S16E06 0750 FKC EKI beta-gamma

location: S17E05

S8155 2023.01.05   35 23 S23W41 0520   DKC beta-gamma
S8157 2023.01.05       S02W25            
13185 2023.01.06
2023.01.09
8 24 18 N20W13 0030 CRO DRI beta-gamma

area: 0090

location: N19W12

13184 2023.01.08
2023.01.08
8 32 14 S13E53 0440 EKI DAC beta-gamma-delta
S8161 2023.01.08       S17W15          
S8162 2023.01.08       S31W09            
13187 2023.01.09
2023.01.10
2 11 5 N13E18 0010 AXX CRO area: 0025
13186 2023.01.09
2023.01.10
5 12 9 N25E65 0100 DSO DAC beta-delta

location: N23E63

S8165 2023.01.09   2   S07W00 0005   BXO  
S8167 2023.01.10   9 5 S17W57 0030   CRO    
S8168 2023.01.10   2 1 S24E82 0020   HRX    
Total spot count: 121 290 163  
Sunspot number: 201 420 273  (total spot count + 10 * number of spotted regions)
Weighted SN: 169 347 220  (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): 221 231 218  

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
2023.01 167.2 (1)   36.5 (2A) / 113.1 (2B) / 140.9 (2C) (113.1 projected, +6.0) (7.9)
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.