Solar Terrestrial Activity Report

Activity chart

Last major update issued on October 27, 2022 at 03:30 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 unsettled on October 26. Solar wind speed at SOHO ranged between 362 and 407 km/sec, both solar wind speed and density increased slowly late in the day. The high latitude magnetometer at Andenes recorded quiet to unsettled levels.

Solar flux density measured at 20h UT on 2.8 GHz was 122.4 - decreasing 14.8 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 117.39). 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: 00001123 (planetary), 00002312 (Boulder), 00001233 (Andenes).

The background x-ray flux is at the class B6 level (GOES 16).

At the time of counting spots (see image time), spots were observed in 7 active regions using 2K resolution (SN: 146) and in 7 active regions using 1K resolution (SN: 108) SDO/HMI images.

Region 13126 [S09W77] decayed slowly and quietly.
Region 13130 [S23W31] developed as new flux emerged in the leading spot section.
Region 13131 [N22E42] developed slowly and quietly.
Region 13132 [S09W30] decayed slowly and quietly.
Region 13133 [N27E60] gained small spots and was the only AR producing C flares. C1 flare: C1.1 @ 22:31 UT

Spotted regions not observed (or interpreted differently) by SWPC:
S7950 [N19W00] was quiet and stable.
S7955 [N13E40] was quiet and stable.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C6.7 22:31 N24E66 13133 GOES16  

Coronal mass ejections (CMEs)

October 24-26: 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 (CH1108) was in an Earth facing position on October 24-25. A recurrent trans equatorial coronal hole (CH1109) will rotate across the central meridian on October 26-28.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle and high latitudes is fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

Quiet to active geomagnetic conditions are likely on October 27-31, first due to effects from CH1108, then on October 29-31 due to effects from CH1109. Minor storm intervals are possible.

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
13126 2022.10.16
2022.10.19
3 3 2 S10W79 0160 DAO CSO location: S10W77

area: 0090

13127 2022.10.17
2022.10.20
      S22W61            
S7937 2022.10.19       N26W53            
S7940 2022.10.20       N11W55            
13130 2022.10.20
2022.10.23
12 27 16 S24W30 0060 DSO DAI area: 0130

location: S23W31

S7943 2022.10.20       S11W58            
S7946 2022.10.21       S27E04            
S7947 2022.10.22       S17W55            
S7948 2022.10.22       N14W28            
S7950 2022.10.23   6 4 N19W00 0015   BXO  
13131 2022.10.23
2022.10.24
7 18 7 N23E44 0170 CAO DKO area: 0300

location: N22E42

S7952 2022.10.23       S14E08            
S7953 2022.10.24       S22W45            
13132 2022.10.24
2022.10.25
2 4 1 S10W31 0010 AXX AXX

location: S09W30

S7955 2022.10.24   7 1 N13E40 0010   BXO  
13133 2022.10.24
2022.10.25
4 11 7 N26E60 0030 CRO DRI area: 0060
Total spot count: 28 76 38  
Sunspot number: 78 146 108  (total spot count + 10 * number of spotted regions)
Weighted SN: 46 99 61  (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): 86 80 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
2022.10 134.1 (1)   73.0 (2A) / 87.0 (2B) / 103.1 (2C) (108.3 projected, +3.1) (10.9)
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.