Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 15, 2023 at 11:35 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 14. Weak CME effects were observed early in the day. A stronger CME was observed arriving at DSCOVR at 17:06 UT and caused minor storming early on January 15. Solar wind speed at SOHO ranged between 404 and 601 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 227.8 - increasing 72.2 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 127.43). The Potsdam WDC planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 9.3). Three hour interval K indices: 33220023 (planetary), 33222223 (Boulder), 54320134 (Andenes).

The background x-ray flux is at the class C4 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 17 active regions using 2K resolution (SN: 451) and in 15 active regions using 1K resolution (SN: 291) SDO/HMI images.

Region 13182 [S17W46] lost some area. Positive polarity flux emerged and spearheaded negative polarity flux in the northern spot section, a magnetic delta formed. Subsequently the region became unstable and produced several C and M flares.
Region 13184 [S13E01] decayed slowly and was mostly quiet.
Region 13185 [N20W68] decayed slowly and quietly.
Region 13186 [N24E10] was mostly quiet and stable despite having a weak magnetic delta in a trailing penumbra. A major flare is possible.
Region 13188 [S24E35] gained spots and was quiet.
Region 13189 [N20W40] decayed slowly and quietly.
Region 13190 [S14E59] has a huge leader spot and could produce a major flare.
Region 13191 [N10E52] developed further and has magnetic delta in a northern penumbra. The region still has a compact spot layout and major flares are possible.
Region 13192 [N18E62] was mostly quiet and stable. M flares are possible.

Spotted regions not observed (or interpreted differently) by SWPC:
S8170 [N19E36] was quiet and stable. The region has reversed polarities.
S8177 [N21E42] was quiet and stable.
S8178 [N10E62] was quiet and stable.
S8179 [S22E50] developed slowly and quietly.
S8181 [S21E42] decayed slowly and quietly.
New region S8182 [S22W18] emerged with many tiny spots.
New region S8183 [S27W64] emerged with a tiny spot.
New region S8184 [S27E11] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C6.2 00:27   13191 GOES16  
M1.3 02:09   13191 GOES16  
C6.5 04:38   13190 GOES16  
C3.7 07:07 behind SW limb S8155 GOES16  
C3.9 08:13   13184 GOES16  
C4.6 10:17   13192 GOES16 simultaneous flare in AR 13182
C7.0 11:06   13182 GOES16  
C6.6 11:28   13182 GOES16  
C6.8 11:42   13190 GOES16  
C4.9 12:07   13182 GOES16  
C4.9 12:46   13182 GOES16  
C5.0 12:54   13182 GOES16  
C5.0 13:50   13182 GOES16  
C5.7/1F 14:39   13182 GOES16  
C6.8 14:58   13182 GOES16  
C5.5 15:33   13182 GOES16  
C4.5 15:54   13190 GOES16  
C4.5 16:32 behind SW limb S8155 GOES16  
C7.4 19:27   13192 GOES16 attributed to AR 13182 by SWPC
C5.7 20:02   13182 GOES16  
M3.5 20:21   13182 GOES16  
M4.6 21:00   13182 GOES16  
C7.3 22:38   13182 GOES16  

Coronal mass ejections (CMEs)

January 12-14: 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 trans equatorial coronal hole (CH1125) will likely become 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 are expected on January 15 due to CME effects. Quiet to unsettled is likely on January 16-17.

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
15 49 24 S18W48 0190 DAI DAI beta-delta

location: S17W46

13185 2023.01.06
2023.01.09
6 10 3 N19W69 0030 CAO BXO

location: N20W68

13184 2023.01.08
2023.01.08
13 45 24 S12W00 0260 EHO FSO beta-gamma

area: 0390

location: S13E01

13187 2023.01.09
2023.01.10
      N16W38         location: N14W35
13186 2023.01.09
2023.01.10
12 39 19 N25E10 0410 EKI EKI beta-delta

location: N24E10

area: 0750

S8165 2023.01.09       S07W52            
13188 2023.01.10
2023.01.12
5 17 11 S23E33 0030 DRI DRI location: S24E35

area: 0080

13189 2023.01.11
2023.01.13
1 3 1 N23W45 0010 AXX BXO location: N20W40
S8170 2023.01.12   4 3 N19E36 0010   BXO reversed polarities
13191 2023.01.12
2023.01.13
9 18 13 N11E55 0150 DAI DAC beta-delta

location: N10E52

area: 0370

13192 2023.01.12
2023.01.13
8 24 11 N19E61 0160 DSI FSI area: 0350

location: N18E62

13190 2023.01.12
2023.01.13
11 29 18 S12E58 0510 EKO EKO location: S14E59

area: 0900

S8174 2023.01.12       N20W49            
S8177 2023.01.13   4 2 N21E42 0010   BXO  
S8178 2023.01.13   4 2 N10E62 0020   AXX  
S8179 2023.01.13   17 6 S22E50 0030   BXO  
S8180 2023.01.13       S18E07          
S8181 2023.01.13   1   S22E42 0002   AXX  
S8182 2023.01.14   15 3 S22W18 0030   CRO    
S8183 2023.01.14   1 1 S27W64 0002   AXX    
S8184 2023.01.14   1   S27E11 0002   AXX    
Total spot count: 80 281 141  
Sunspot number: 170 451 291  (total spot count + 10 * number of spotted regions)
Weighted SN: 133 327 187  (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): 187 248 233  

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
2023.01 179.6 (1)   58.6 (2A) / 129.7 (2B) / 145.1 (2C) (113.1 projected, +6.0) (8.2)
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.