Solar Terrestrial Activity Report

Activity chart

Last major update issued on October 28, 2022 at 09:50 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 unsettled on October 27, likely due to effects from CH1108. Solar wind speed at SOHO ranged between 372 and 482 km/sec. The high latitude magnetometer at Andenes recorded quiet to active levels.

Solar flux density measured at 20h UT on 2.8 GHz was 129.7 - decreasing 7.4 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 117.44). The Potsdam WDC planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 8.9). Three hour interval K indices: 21233322 (planetary), 11332322 (Boulder), 42124332 (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 9 active regions using 2K resolution (SN: 197) and in 7 active regions using 1K resolution (SN: 118) SDO/HMI images.

Region 13130 [S23W43] developed early in the day, then decayed slowly after noon. C1 flares: C1.7 @ 01:03, C1.1 @ 08:56 UT
Region 13131 [N22E29] decayed slowly and quietly. C1 flare: C1.3 @ 10:01 UT
Region 13132 [S10W48] decayed early in the day while slow development was observed after noon.
Region 13133 [N27E47] developed slowly and gained a small magnetic delta near the center. C1 flare: C1.1 @ 04:39 UT

Spotted regions not observed (or interpreted differently) by SWPC:
S7950 [N18W18] was quiet and stable.
S7955 [N12E48] developed slowly as new flux emerged after noon.
New region S7957 [S16W49] emerged with a few spots.
New region S7958 [N26E77] rotated into view with a tiny spot.
New region S7959 [N16E71] rotated into view with a tiny spot.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.3 01:26   13133 GOES16 simultaneous flare in AR 13130
C2.2 01:57   13133 GOES16  

Coronal mass ejections (CMEs)

October 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 (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 poor to fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

Quiet to active geomagnetic conditions are likely on October 28-31, 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
1     S09W93 0050 HSX     rotated out of view
13127 2022.10.17
2022.10.20
      S22W75            
13130 2022.10.20
2022.10.23
9 34 20 S25W44 0090 DAO DAI area: 0180

location: S23W43

S7946 2022.10.21       S27W09            
S7948 2022.10.22       N14W41            
S7950 2022.10.23   7 3 N18W18 0015   BXO  
13131 2022.10.23
2022.10.24
4 15 4 N23E29 0190 CSO CHO area: 0270

location: N22E29

S7952 2022.10.23       S14W18            
13132 2022.10.24
2022.10.25
2 7 3 S10W47 0010 BXO CRO

location: S10W48

S7955 2022.10.24   13 4 N12E28 0020   BXO  
13133 2022.10.24
2022.10.25
6 23 12 N26E46 0030 CRO DAI beta-delta

area: 0090

location: N27E47

S7957 2022.10.27   6 2 S16W49 0013   CRO    
S7958 2022.10.27   1   N26E77 0002   AXX    
S7959 2022.10.27   1   N27E47 0001   AXX    
Total spot count: 22 107 48  
Sunspot number: 72 197 118  (total spot count + 10 * number of spotted regions)
Weighted SN: 40 133 72  (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): 79 108 94  

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
2022.10 134.0 (1)   75.3 (2A) / 86.5 (2B) / 103.9 (2C) (108.3 projected, +3.1) (10.8)
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.