Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 6, 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 5 due to weak CME effects. Solar wind speed at SOHO ranged between 319 and 440 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 154.3 - increasing 5.2 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 125.21). The Potsdam WDC planetary A index was 7 (STAR Ap - based on the mean of three hour interval ap indices: 7.1). Three hour interval K indices: 01113323 (planetary), 01123221 (Boulder), 01102454 (Andenes).

The background x-ray flux is at the class C1 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 12 active regions using 2K resolution (SN: 274) and in 9 active regions using 1K resolution (SN: 168) SDO/HMI images.

Region 13176 [N18W74] decayed further and was mostly quiet. C1 flares: C1.3 @ 12:54 UT
Region 13177 [S18W34] decayed further and was mostly quiet.
Region 13181 [S18E18] developed early in the the day, then decayed slowly.
New region 13182 [S17E72] rotated into view on January 4 and was numbered the next day by SWPC. The region may have a magnetic delta in a southern penumbra. That location appeared to be the source of an X1.2 flare at 00:57 UT on January 6. Further major flares are possible. C1 flares: C1.4 @ 01:42, C1.8 @ 15:51, C1.7 @ 19:15, C1.4 @ 21:45 UT
New region 13183 [S17W08] was observed with tiny spots on January 3, then developed quickly on January 5 and was numbered by SWPC. C and minor M class flares are possible.

Spotted regions not observed (or interpreted differently) by SWPC:
S8133 [N17W10] decayed slowly and was mostly quiet.
S8135 [N21W08] decayed slowly and quietly.
S8137 [S26W20] decayed slowly and quietly.
S8153 [S10E13] was quiet and stable.
New region S8155 [S22E22] emerged southeast of AR 13181 and produced a few flares.
New region S8156 [S27W70] emerged with a tiny spot.
New region S8157 [S02E40] emerged with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.0 02:37   13182 GOES16  
C2.6 02:49   13182 GOES16 wrongly attributed to AR 13177 by SWPC
C2.2 03:52   13182 GOES16  
C2.2 04:23   13182 GOES16  
C2.0 04:53   13182 GOES16  
C2.6 05:13   13182 GOES16  
C2.6 08:13   S8133 GOES16  
C6.8 09:14   13182 GOES16 LDE
C2.1 22:22 S24E22 S8155 GOES16  
C2.4 22:57 S18W07 13183 GOES16  

Coronal mass ejections (CMEs)

January 3-5: 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 is likely too far to the north to cause geomagnetic effects, it will rotate 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. Propagation on long distance northeast-southwest paths is poor.

Forecast

Quiet to unsettled conditions are expected on January 6-7 becoming quiet on January 8.

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
13176 2022.12.25
2022.12.26
1 5 1 N19W71 0030 HSX CSO

location: N18W74

area: 0050

13177 2022.12.27
2022.12.28
10 24 11 S18W36 0090 CAO CAO  
S8133 2022.12.29   25 13 N17W10 0170   DSO  
13180 2022.12.30 11     N19W10 0180 CSO       SWPC consider AR S8133 and S8135 to be one region
S8135 2022.12.30   7 2 N21W08 0150   CSO  
S8137 2022.12.30   3   S26W20 0005   AXX  
13181 2022.12.31
2023.01.01
12 24 12 S18E18 0080 DAO DAO area: 0130
S8140 2022.12.31       N28W35            
S8142 2023.01.01       N14W55            
S8143 2023.01.01       N21W28            
S8144 2023.01.01       N27W57            
S8146 2023.01.02       S13W01            
S8149 2023.01.03       N33W11            
S8150 2023.01.03       N14E06            
13183 2023.01.03
2023.01.05
5 26 17 S17W08 0030 CRO DAI area: 0140
S8153 2023.01.04   2 1 S10E13 0003   BXO  
13182 2023.01.04
2023.01.05
4 21 13 S17E72 0280 DKI EKI beta-gamma-delta?

area: 0530

S8155 2023.01.05   15 8 S22E22 0050   DRO    
S8156 2023.01.05   1   S27W70 0002   AXX    
S8157 2023.01.05   1   S02E40 0001   AXX    
Total spot count: 43 154 78  
Sunspot number: 103 274 168  (total spot count + 10 * number of spotted regions)
Weighted SN: 76 197 121  (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): 113 143 134  

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
2023.01 150.6 (1)   15.0 (2A) / 93.2 (2B) / 137.9 (2C) (113.1 projected, +6.0) (10.4)
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.