Solar Terrestrial Activity Report

Activity chart

Last major update issued on October 24, 2022 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 (October 6, 2022)
Solar cycle Solar cycles 23-25 (October 1, 2022) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (October 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 (October 1, 2022) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (October 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 active on October 23 due to effects from CH1107. Solar wind speed at SOHO ranged between 353 and 617 km/sec. The high latitude magnetometer at Andenes recorded quiet to major storm levels.

Solar flux density measured at 20h UT on 2.8 GHz was 108.4 - decreasing 26.7 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 117.25). The Potsdam WDC planetary A index was 15 (STAR Ap - based on the mean of three hour interval ap indices: 15.4). Three hour interval K indices: 32212444 (planetary), 22313433 (Boulder), 52312365 (Andenes).

The background x-ray flux is at the class B4 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 11 active regions using 2K resolution (SN: 182) and in 8 active regions using 1K resolution (SN: 107) SDO/HMI images.

Region 13126 [S10W37] developed slowly and quietly.
Region 13127 [S21W17] decayed slowly and quietly.
Region 13128 [S16W82] decayed slowly and quietly.
Region 13129 [S26W83] decayed slowly and quietly.
New region 13130 [S24E08] was first observed with spots on October 20 and developed slowly on October 23 when the region was numbered by SWPC. C1 flares: C1.9 @ 16:26, C1.2 @ 21:15 UT

Spotted regions not observed (or interpreted differently) by SWPC:
S7943 [S11W19] was quiet and stable.
S7948 [N14E11] decayed slowly and quietly.
New region S7949 [S10W68] emerged before noon with a few tiny spots.
New region S7950 [N16E31] was observed with tiny spots in an old plage area.
New region S7951 [N22E83] rotated into view with tiny spots.
New region S7952 [S14E47] emerged with tiny spots.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.5 18:22   13130 GOES16  

Coronal mass ejections (CMEs)

October 21-23: 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 southern hemisphere coronal hole (CH1107) was Earth facing on October 20-22. A recurrent northern hemisphere coronal hole (CH1108) will likely rotate into an Earth facing position on October 24-25.

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 active geomagnetic conditions are likely on October 24-25 due to effects from CH1107. October 26 could see quiet conditions. Then on October 27-28 quiet to active conditions are likely due to effects from CH1108.

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
13129 2022.10.10
2022.10.22
1 1   S26W86 0010 AXX AXX  
13121 2022.10.11
2022.10.13
      N24W81          

location: N22W78

13125 2022.10.13
2022.10.17
      S22W76            
13126 2022.10.16
2022.10.19
6 20 9 S10W38 0030 CSO DAO location: S10W37

area: 0090

13127 2022.10.17
2022.10.20
1 3   S22W19 0010 AXX AXX  
S7936 2022.10.19       S19W52            
S7937 2022.10.19       N26W14            
S7938 2022.10.20       N21W56            
S7939 2022.10.20       S12W23            
S7940 2022.10.20       N11W16            
S7941 2022.10.20       N30W25            
13130 2022.10.20
2022.10.23
5 30 12 S24E09 0020 CRO DRI  
S7943 2022.10.20   2 1 S11W19 0005   AXX  
13128 2022.10.21
2022.10.21
2 1 1 S17W81 0020 CAO AXX area: 0005
S7945 2022.10.21       N18W36            
S7946 2022.10.21       S27E43            
S7947 2022.10.22       S17W16            
S7948 2022.10.22   1 1 N14E11 0004   AXX  
S7949 2022.10.23   4 1 S10W68 0010   BXO    
S7950 2022.10.23   6   N16E31 0008   BXO    
S7951 2022.10.23   2 1 N22E83 0010   HRX    
S7952 2022.10.23   2 1 S14E47 0004   BXO    
Total spot count: 15 72 27  
Sunspot number: 65 182 107  (total spot count + 10 * number of spotted regions)
Weighted SN: 28 83 38  (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): 72 100 86  

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
2021.03 76.0 75.2 17.2 21.7 (+2.7) 10.17
2021.04 75.9 76.4 24.5 24.8 (+3.1) 8.40
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 (74.2 projected, +5.3) 11.79
2022.05 133.8 136.8 96.5 (80.6 projected, +6.4) 7.48
2022.06 116.1 119.8 70.3 (86.5 projected, +5.9) 8.20
2022.07 125.4 129.5 91.4 (93.7 projected, +7.2) 9.51
2022.08 114.2 117.1 75.4 (100.2 projected, +6.5) 10.92
2022.09 135.1 136.5 96.3 (105.2 projected, +5.0) 12.18
2022.10 136.2 (1)   66.7 (2A) / 89.9 (2B) / 109.0 (2C) (108.3 projected, +3.1) (11.8)
2022.11       (111.2 projected, +2.9)  
2022.12       (115.9 projected, +4.7)  
2023.01       (122.0 projected, +6.1)  
2023.02       (127.0 projected, +5.0)  
2023.03       (130.0 projected, +3.0)  
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.