Solar Terrestrial Activity Report

Activity chart

Last major update issued on December 28, 2022 at 11:50 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 (December 4, 2022)
Solar cycle Solar cycles 23-25 (December 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (December 1, 2022) 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 (December 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (December 1, 2022) 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 minor storm on December 27 due to CME effects. Solar wind speed at SOHO ranged between 491 and 589 km/sec. The high latitude magnetometer at Andenes recorded unsettled to major storm levels.

Solar flux density at 20h UT on 2.8 GHz was not provided by DRAO/Penticton. Instead 140.3 (estimated from Almaty data) is a replacement value - increasing 29.7 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 123.73). The Potsdam WDC planetary A index was 27 (STAR Ap - based on the mean of three hour interval ap indices: 26.8). Three hour interval K indices: 45544522 (planetary), 35445521 (Boulder), 65533654 (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 11 active regions using 2K resolution (SN: 249) and in 10 active regions using 1K resolution (SN: 162) SDO/HMI images.

Region 13169 [N21W59] produced several C flares and one minor M class. Further minor M class flares are possible, however, the region is slowly decaying.
Region 13170 [S14W53] was quiet and stable.
Region 13171 [N24W37] decayed slowly and quietly.
Region 13172 [S36W08] decayed slowly and quietly.
Region 13173 [N23E11] was quiet and stable.
Region 13175 [S21E29] decayed slowly and quietly.
Region 13176 [N18E50] developed further and matured. Flare frequency decreased significantly as the region simplified magnetically.

Spotted regions not observed (or interpreted differently) by SWPC:
S8122 [N19W39] decayed slowly and quietly.
New region S8127 [S18E82] rotated partly into view as a a compact region and may have M class flare potential as several C flares were observed.
New region S8128 [N05E31] emerged with a tiny spot.
New region S8129 [N18W18] emerged with tiny spots.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C6.4 00:44   13176 GOES16  
M2.0 00:54   13176 GOES16  
C3.9 01:45   13176 GOES16  
C3.9 02:26   13176 GOES16  
C4.8 02:47   13176 GOES16  
C5.3 03:00   13176 GOES16  
C7.4 03:09   13176 GOES16  
C6.2 03:20   13169 GOES16 simultaneous flare in AR 13176 which was by far the brightest
C3.3 04:28   13176 GOES16  
C3.1 04:45   13176 GOES16 attributed to AR 13169 by SWPC, where a much weaker event was in progress
C2.5 05:25   13176 GOES16  
C4.5 07:12   S8127 GOES16  
M1.0/2N 08:15   13176 GOES16  
C4.2 09:21 N23W43 13169 GOES16  
C3.3 12:56   S8127 GOES16  
M1.2/1B 16:26   13169 GOES16  
C4.7 17:30 behind NE limb   GOES16 incorrectledly attributed to AR 13169 by SWPC
C3.0 19:59   S8127 GOES16 LDE
C4.5 20:16   S8127 GOES16  
C3.9 20:37   S8127 GOES16  
C2.7 21:48   13176 GOES16  

Coronal mass ejections (CMEs)

December 25-27: 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 recurrent northern hemisphere coronal hole (CH1122) will rotate across the central meridian on December 25-27.

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 geomagnetic conditions are expected for December 28. Effects from CH1122 could reach Earth on December 29 and cause quiet to minor storm conditions until December 31.

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
13169 2022.12.16
2022.12.17
17 46 20 N22W60 0490 FKC FAI

beta-gamma

area: 0430

location: N21W59

13170 2022.12.17
2022.12.17
  7 2 S19W58 0014   BXO

location: S14W53

13171 2022.12.18
2022.12.19
5 8 4 N23W39 0090 CAO CAO location: N24W37

area: 0120

13172 2022.12.20
2022.12.21
  13 3 S36W04 0020   BXO location: S36W08
13173 2022.12.22
2022.12.22
1 10 3 N25E10 0090 HSX CAO

area: 0080

location: N23E11

S8115 2022.12.22       S03W35            
S8116 2022.12.23       S17W48            
S8117 2022.12.23       S22W34            
13175 2022.12.24
2022.12.25
4 11 5 S20E29 0010 AXX CRO location: S21E29

area: 0025

S8120 2022.12.24       N20W09            
S8121 2022.12.24       S07W08            
S8122 2022.12.25   8 4 N19W39 0015   BXO  
S8123 2022.12.25       S17W08            
13176 2022.12.25
2022.12.26
12 29 17 N19E50 0400 DKI DKI location: N18E50

area: 0580

S8127 2022.12.27   4 3 S18E82 0350   DKC    
S8128 2022.12.27   1   N05E31 0003   AXX    
S8129 2022.12.27   2 1 N18W18 0001   AXX  

 

Total spot count: 39 139 62  
Sunspot number: 89 249 162  (total spot count + 10 * number of spotted regions)
Weighted SN: 69 177 100  (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): 98 137 130  

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
2021.05 75.3 77.1 21.2 25.8 (+1.0) 6.50
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 64.8 (+4.7) 10.46
2022.03 117.0 115.8 78.6 68.9 (+4.1) 10.20
2022.04 130.8 131.7 84.0 73.1 (+4.2) 11.79
2022.05 133.8 136.8 96.5 77.3 (+4.2) 7.48
2022.06 116.1 119.8 70.3 (80.7 projected, +3.6) 8.20
2022.07 125.4 129.5 91.4 (85.7 projected, +5.0) 9.51
2022.08 114.2 117.1 75.4 (91.4 projected, +5.7) 10.92
2022.09 135.1 136.5 96.3 (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
2022.12 144.7 (1)   96.6 (2A) / 111.5 (2B) / 124.4 (2C) (107.1 projected, +4.8) (10.6)
2023.01       (113.1 projected, +6.0)  
2023.02       (118.1 projected, +5.0)  
2023.03       (121.2 projected, +3.1)  
2023.04       (126.6 projected, +5.4)  
2023.05       (132.4 projected, +5.8)  
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.