Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 21, 2022 at 08:55 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 1, 2022)
Solar cycle Solar cycles 23-25 (January 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (January 1, 2022) Noon SDO sunspot count 1K image / 4K (*)
  Solar cycles 1-24 (June 1, 2020) POES auroral activity level October 2009 - December 2012]
  Comparison of cycles 21-25 (January 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (January 1, 2022) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (August 22, 2021) 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 20. The high latitude magnetometer at Andenes recorded quiet to minor storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 99.3 - decreasing 31.3 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 83.13). The Potsdam WDC planetary A index was 4 (STAR Ap - based on the mean of three hour interval ap indices: 4.1). Three hour interval K indices: 30000001 (planetary), 41000111 (Boulder), 50000002 (Andenes).

The background x-ray flux is at the class B1 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 9 active regions using 2K resolution (SN: 114) and in 5 active regions using 1K resolution (SN: 60) SDO/HMI images.

Region 12927 [S20W77] decayed slowly and quietly.
Region 12929 [N08W85] rotated partly out of view and produced a major flare which was the source of a minor proton event. C1 flares: C1.1 @ 02:14, C1.6 @ at 02:46 UT.
Region 12930 [N21W84] rotated partly out of view and was quiet.
Region 12932 [N30W02] was quiet and stable.
Region 12933 [S19W48] decayed slowly and quietly.
New region 12934 [S24E68] rotated into view on January 19 and was numbered the next day by SWPC.

Spotted regions not observed (or interpreted differently) by SWPC:
S7304 [S20W09] was quiet and stable.
S7305
[N20E23] was quiet and stable.
New region S7308 [S19E77] rotated into view with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
M5.5/1F 06:01 N08W68 12929 GOES16 CME, type II/IV radio sweeps, proton event

Coronal mass ejections (CMEs)

January 18: A CME was observed off the northwest limb and part of the southwest limb after an M1.5 event in AR 12929 peaking at 17:44 UT. Due to missing LASCO imagery for a couple of hours after this event, it is uncertain whether or not there were any Earth direct components. There is a chance of weak geomagnetic effects from the CME on January 22.
January 19-20
: 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 small, recurrent northern hemisphere coronal hole (CH1055) was in an Earth facing position on January 20. Another northern hemisphere coronal hole (CH1056) will rotate across the central meridian on January 21-22.

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

The geomagnetic field is expected to be quiet to unsettled on January 21-22 and become quiet to active on January 23-25 due to effects from CH1055 and CH1056.

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
12927 2022.01.08
2022.01.09
1 1 1 S21W79 0001 AXX AXX location: S20W77

area: 0003

12930 2022.01.11
2022.01.13
2 1   N22W87 0080 DAO HSX

location: N21W84

area: 0150

12929 2022.01.11
2022.01.13
2 1   N08W88 0100 DAO HAX

reversed polarities

12933 2022.01.13
2022.01.16
4 8 4 S22W49 0080 CAO HAX location: S19W48
12932 2022.01.14
2022.01.15
  6 2 N32W07 0010   AXX location: N29W02
S7294 2022.01.14       S28W24            
S7295 2022.01.14       S28W02          
S7297 2022.01.14       N32W53            
S7299 2022.01.15       N02W41           SC24 group
S7300 2022.01.16       N18W35            
S7301 2022.01.18       S14W10            
S7302 2022.01.18       N22E52          
12934 2022.01.19
2022.01.20
1 1 1 S24E69 0090   HSX area: 0170
S7304 2022.01.19   1   S20W09 0002   AXX  
S7305 2022.01.19   4 2 N20E23 0007   AXX  
S7306 2022.01.19       N18W04          
S7307 2022.01.19       S10E19          
S7308 2022.01.20   1   S190E77 0003   AXX    
Total spot count: 10 24 10  
Sunspot number: 60 114 60  (total spot count + 10 * number of spotted regions)
Weighted SN: 30 44 30  (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): 66 63 48  

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
2020.06 69.5 71.7 5.8 7.9 (+2.3) 3.75
2020.07 69.5 71.8 6.3 9.0 (+1.1) 4.28
2020.08 71.6 73.4 7.6 9.5 (+0.5) 5.68
2020.09 70.7 71.4 0.7 10.5 (+1.0) 8.59
2020.10 74.6 74.2 14.6 11.9 (+1.4) 6.13
2020.11 89.9 88.0 34.5 13.6 (+1.7) 4.77
2020.12 86.9 84.2 23.1 15.3 (+1.7) 4.72
2021.01 76.0 73.6 10.4 17.3 (+2.0) 4.39
2021.02 74.3 72.4 8.3 19.1 (+1.8) 9.50
2021.03 76.0 75.2 17.3 21.8 (+2.7) 10.17
2021.04 75.9 76.4 24.5 24.9 (+3.1) 8.40
2021.05 75.3 77.1 21.2 25.9 (+1.0) 6.50
2021.06 79.4 81.8 25.3 27.8 (+1.9) 5.52
2021.07 81.0 83.6 34.4 (31.8 projected, +4.0) 5.51
2021.08 77.7 79.7 22.4 (36.5 projected, +4.7) 6.19
2021.09 87.0 88.2 51.5 (42.2 projected, +5.7) 6.33
2021.10 88.9 88.3 38.1 (46.6 projected, +4.4) 7.38
2021.11 86.2 84.4 35.1 (51.2 projected, +4.6) 9.83
2021.12 103.0 99.8 67.6 (57.0 projected, +5.8) 6.40
2022.01 101.6 (1)   36.8 (2A) / 57.1 (2B) / 74.8 (2C) (60.6 projected, +3.6) (9.0)
2022.02       (65.4 projected, +4.8)  
2022.03       (70.8 projected, +5.4)  
2022.04       (75.9 projected, +5.1)  
2022.05       (82.3 projected, +6.4)  
2022.06       (88.2 projected, +5.9)  

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.