Solar Terrestrial Activity Report

Activity chart

Last major update issued on October 17, 2022 at 06:40 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 16 under the influence of coronal hole effects. Solar wind speed at SOHO ranged between 542 and 670 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 119.2 - decreasing 8.7 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 116.62). The Potsdam WDC planetary A index was 14 (STAR Ap - based on the mean of three hour interval ap indices: 14.1). Three hour interval K indices: 32234324 (planetary), 21234323 (Boulder), 52234336 (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: 178) and in 9 active regions using 1K resolution (SN: 132) SDO/HMI images.

Region 13119 [N29W78] decayed slowly and quietly.
Region 13121 [N23E14] developed slowly late in the day.
Region 13122 [N24W40] developed slowly and quietly.
Region 13123 [N27W66] developed slowly producing a few low level C flares. C1 flares: C1.5 @ 14:36, C1.8 @ 16:06 UT
New region 13124 [S35W40] emerged on October 14 and was observed by SWPC 2 days later. The region developed quickly on October 16 and has minor polarity intermixing.

Spotted regions not observed (or interpreted differently) by SWPC:
S7918 [S29W03] was quiet and stable.
S7921 [S23E07] was quiet and stable.
S7930 [S25E13] was quiet and stable.
New region S7934 [S10E57] emerged with tiny spots.

A long duration C1.2 event peaking at 12:52 UT, the source was AR S7901 behind the northwest limb. The same region produced a C1.6 flare at 19:24 UT.

C2+ flares:

Magnitude Peak time (UT) Location Source Recorded by Comment
           

Coronal mass ejections (CMEs)

October 14-16: 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 and poorly defined trans equatorial coronal hole (CH1106) closed on October 16 as it was rotating across the central meridian. A southern hemisphere coronal hole (CH1107) will likely be Earth facing on October 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 to fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

Quiet to unsettled geomagnetic conditions are expected on October 17 becoming quiet on October 18-19. Quiet to unsettled conditions are possible on October 20 due to effects from CH1106.

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
13118 2022.10.05
2022.10.06
      N09W75          

location: N08W70

13119 2022.10.06
2022.10.07
3 7 4 N29W82 0030 CSO CRO

location: N29W78

S7918 2022.10.10   6 1 S29W03 0010   AXX  
13121 2022.10.11
2022.10.13
  3 2 N24E17 0008   BXO

location: N24E14

S7921 2022.10.11   4 2 S23E07 0008   BXO  
S7922 2022.10.11       S14E04          
S7923 2022.10.12       N15W20            
S7924 2022.10.12       S20W33            
S7925 2022.10.12       S27W55            
S7927 2022.10.13       N36W38          
13123 2022.10.13
2022.10.15
6 16 8 N27W66 0030 CAO DRI area: 0060
13122 2022.10.13
2022.10.15
5 16 7 N25W43 0020 CRO DRI area: 0050
S7930 2022.10.13   8 4 S25E13 0020   BXO  
S7931 2022.10.14       S13W21            
13124 2022.10.14
2022.10.16
5 24 12 S35W40 0030 DRO DAI beta-gamma

area: 0180

S7933 2022.10.14       S13W21            
S7934 2022.10.16   4 2 S10E57 0010   CRO    
Total spot count: 19 88 42  
Sunspot number: 59 178 132  (total spot count + 10 * number of spotted regions)
Weighted SN: 35 105 59  (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): 65 98 106  

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
2022.10 146.4 (1)   53.9 (2A) / 104.4 (2B) / 114.4 (2C) (108.3 projected, +3.1) (12.9)
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.