Solar Terrestrial Activity Report

Activity chart

Last major update issued on February 8, 2025 at 09:20 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 (February 7, 2025)
Solar cycle Solar cycles 23-25 (February 1, 2025) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (February 1, 2025) Noon SDO sunspot count 1K image / 4K (*)
  Solar cycles 1-24 (August 1, 2020) POES auroral activity level [October 2009 - December 2012]
  Comparison of cycles 21-25 (February 1, 2025) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (February 1, 2025) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (January 11, 2025) 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
Calculating the Strength of Solar Cycle 25 Using 365-day Smoothing

Recent activity

The geomagnetic field was at very quiet levels on February 7. Solar wind speed at SOHO ranged between 334 and 487 km/sec, averaging 404 km/sec (-44 km/sec compared to the previous day. The high latitude magnetometer at Andenes recorded quiet to unsettled levels. The above 10 MeV proton flux was at background levels all day.

Solar flux density measured at 20h UT on 2.8 GHz was 181.6 - increasing 25.6 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 193.34. In comparison SC24 peaked on June 28, 2014 at 145.50 while SC23 peaked on February 23, 2002 at 198.15. Current SC25 peak: 193.35 on August 7, 2024 (subtracting a base solar flux level of 65, this is +59.44% compared to the SC24 peak and -3.61% compared to the SC23 peak). The Potsdam WDC planetary A index was 2 (STAR Ap - based on the mean of three hour interval ap indices: 2.5). Three hour interval K indices: 10111100 (planetary), 00001101 (Boulder), 30000000 (Andenes).

The background x-ray flux is at the class C1 level (GOES 18).

At the time of counting spots (see image time), spots were observed in 14 active regions using 2K resolution (SN: 246) and in 12 active regions using 1K resolution (SN: 173) SDO/HMI images.

AR 13976 [N11W53] decayed slowly and quietly.
AR 13977 [N19W67] decayed substantially and was quiet after noon.
AR 13978 [N10W54] decayed slowly and was quiet.
AR 13983 [N05E19] was quiet and stable.
AR 13985 [N23W22] was quiet and stable.
AR 13986 [N06E44] was mostly quiet and stable.
AR 13987 [S09E53] was quiet and stable.
New AR 13988 [S19W09] was first observed with spots on February 2 and was numbered by SWPC 5 days later.

Spotted regions not observed (or interpreted differently) by SWPC/USAF:
S10753 [N06W35] decayed slowly and quietly.
S10759 [N07W43] still has 2 magnetic delta configurations and could produce another major flare. This is the spot group SWPC currently has as AR 13981.
S10762 [N12W49] gained area and produced a few flares
S10776 [S27W19] was quiet and stable.
New region S10777 [S04W37] emerged with tiny spots.
New region S10779 [N23E08] emerged with a tiny spot.

C2+ flares

Magnitude Peak time (UT) Location Source Recorded by Comment
C2.9 01:06   S10759 GOES16  
C3.8 01:17   13977 GOES16  
C2.9 01:34   13976 GOES16  
C3.0 01:43   13977 GOES16  
C3.9 02:21   13977 GOES16  
C2.1 02:48     GOES16  
C2.2 03:41   S10759 GOES16  
C3.2 04:31   S10762 GOES16  
C2.4 04:50   S10759 GOES16  
C2.4 05:11   S10759 GOES16  
C3.1 05:20   S10759 GOES16  
C3.3 05:30   S10759 GOES16  
C2.7 05:47   S10759 GOES16  
M1.6 06:30   S10759 GOES16  
M1.1 06:46   S10759 GOES16  
M1.0 06:51   S10759 GOES16  
M3.2 07:21   S10759/S10753 GOES16  
M1.2 07:52   13977 GOES16  
M1.2 08:03   S10762 GOES16  
M7.6 09:21   S10762 GOES16  
C5.5 10:15   S10762 GOES16  
C4.0 10:34   S10762 GOES16  
C2.8 11:24   S10759 GOES16  
C2.7 11:41     GOES16  
C2.4 12:04   S10759 GOES16  
C9.1 12:13   S10762 GOES16  
C2.2 12:40     GOES16  
C2.7 12:51   S10759 GOES16  
C2.1 13:55     GOES16  
C3.0 14:13   S10759 GOES16  
C3.1 14:19   13976 GOES16  
C2.5 15:34   S10759 GOES16  
C2.4 15:41   S10759 GOES16  
C2.1 17:09   13986 GOES16  
C2.1 17:19   13986 GOES16  
C2.2 17:46   S10759 GOES16  
C2.1 19:23   S10759 GOES16  
C2.9 23:13   S10762 GOES16  

Coronal mass ejections (CMEs)

February 5-7: No obviously Earth directed CMEs.

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 negative polarity trans equatorial coronal hole (CH1269) will rotate across the central meridian on February 6-8. A recurrent negative polarity southern hemisphere coronal hole (CH1270) will likely rotate into an Earth facing position on February 9-11.

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

The geomagnetic field is expected to be at quiet levels on February 8-9. Quiet to minor storm levels are likely on February 10-12 due to effects from CH1269.

Coronal holes (1) Coronal mass ejections (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
STAR SWPC STAR Current Previous
2K 1K
13974 2025.01.25
2025.01.26
1     S15W89 0010 AXX      

was AR S10740

location: S14W80

spotless

13976 2025.01.27
2025.01.27
1 2 1 N11W68 0080 HSX CSO    

location: N10W68

area: 0140

13977 2025.01.27
2025.01.27
1 2 1 N18W68 0010 AXX HRX    

location: N19W67

area: 0020

13978 2025.01.28
2025.01.28
6 6 3 N14W53 0280 CKO HAX    

area: 0180

location: N10W54

apparantly SWPC decided to include the spots of AR S10762 on 2025.02.07

13980 2025.01.29
2025.01.30
      S12W51           was AR S10752

location: S12W46

S10753 2025.01.29   4 4 N06W35 0050   DRO     reinstated on 2025.02.02 due to SWPC using AR 13981 for two different spot groups
13981 2025.01.30 40     N08W42 0420 EKC       see AR S10753/S10759

This was initially AR S10753. SWPC moved the location of AR 13981 to that of AR S10759, a separate spot group which emerged on January 31.

13982 2025.01.30       N21W51           was AR S10754

location: N23W50

13984 2025.01.30
2025.02.04
8     N15W52 0060 DAO       was AR S10755

spotless

SWPC decided to include the spots of AR S10762 in this AR, however, that means those spots are now included in two different regions at the same time, see AR 13978. What a mess!

S10756 2025.01.30       S12W58            
S10759 2025.01.31   42 21 N07W43 1010   EKC     beta-gamma-delta

This is currently AR 13981 to SWPC

S10761 2025.01.31       S21W54            
S10762 2025.02.01   19 10 N12W49 0120   DAI     beta-gamma
13985 2025.02.01
2025.02.04
3 9 3 N23W23 0020 DRO DRO     was AR S10763

location: N23W22

13988 2025.02.02
2025.02.07
4 6 3 S20W09 0010 BXO CRO     was AR S10766

location: S19W09

area: 0020

S10767 2025.02.02       S20W27            
S10768 2025.02.03       N20W25            
13983 2025.02.03
2025.02.04
2 6 3 N06E18 0040 CAO DSO     was AR S10769

area: 0070

location: N05E19

S10770 2025.02.03       N25W21            
13986 2025.02.04
2025.02.05
1 1 1 N06E42 0170 HSX HSX     was AR S10772

area: 0200

location: N06E44

13987 2025.02.05
2025.02.06
2 2 2 S09E50 0020 HRX HAX     was AR S10774

area: 0040

S10775 2025.02.05       S43E08            
S10776 2025.02.06   4 1 S27W19 0007   BXO      
S10777 2025.02.07   2   S04W37 0002   BXO      
S10779 2025.02.07   1   N23E08 0001   AXX      
Total spot count: 69 106 53  
Sunspot number: 179 246 173  (total spot count + 10 * number of spotted regions)
Weighted SN: 115 158 105  (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): 197 135 138  

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 (SC24 solar max) 7.88
2017.09 91.3 92.3 43.6 18.2 (-1.3) 18.22
(SC24 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
2023.06 161.7 166.8 160.5 125.3 (+1.1) 8.95
2023.07  176.4 182.2 160.0 124.6 (-0.7) 8.15
2023.08  153.7 157.6 114.8 124.3 (-0.3) 7.19
2023.09  154.4 156.0 134.2 124.0 (-0.3) 14.26
2023.10  142.8 141.9 99.4 124.8 (+0.8) 8.16
2023.11 153.5 150.2 105.4 127.9 (+3.1) 12.20
2023.12 151.1 146.4 114.2 129.5 (+1.6) 9.60
2024.01 164.6 159.3 126.0 131.2 (+1.7) 5.46
2024.02 172.5 168.3 123.0 136.9 (+5.7) 5.31
2024.03 154.4 152.9 103.7 141.4 (+4.5) 11.03
2024.04 161.3 162.6 137.0 144.5 (+3.1) 9.69
2024.05 187.7 191.9 172.1 149.1 (+4.6) 23.56
(SC25 peak)
2024.06 184.3 190.2 164.1 152.7 (+3.6) 10.24
2024.07 196.6 203.0 196.8 154.9 (+2.3) 7.13
2024.08  246.1
(cycle peak)
252.2 216.0  (SC25 peak) (156.2 projected, +1.3) 15.96
2024.09 195.7 197.8 141.1 (158.3 projected, +2.1) 15.36
2024.10 221.0 219.6 166.3 (159.1 projected, +0.8) 18.99
2024.11 199.6 195.3 152.5 (156.5 projected, -2.6) 9.33
2024.12 197.3 191.2 154.5 (152.1 projected, -4.4) 8.42
2025.01 190.3 184.2  137.0 (145.8 projected, -6.3) 13.17
2025.02  198.2 (1)   41.3 (2A) / 165.0 (2B) / 168.5 (2C) (137.2 projected, -8.6) (9.2)
2025.03       (130.8 projected, -6.4)  
2025.04       (126.2 projected, -4.6)  
2025.05       (120.9 projected, -5.3)  
2025.06       (115.6 projected, -5.3)  
2025.07       (110.9 projected, -4.7)  

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 27 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: WDC-SILSO, Royal Observatory Of Belgium, Brussels

Solar cycles 24-25

Smoothed SF and sunspot numbers

Update on the progress of solar cycle 25 as of December 30, 2024

Sunspot activity increased again during the second half of December 2024, and this will be the eighth consecutive month with average solar flux above 180. The average solar flux at 1 AU since May 1, 2024 is 205. There is an increasing chance solar cycle 25 could have a higher 1 year solar flux average than solar cycle 23. The above plot displays a projected peak for the ISN 365d smoothed sunspot number on October 12, 2024. All the other smoothed sunspot numbers as well as the smoothed 365d solar flux have projected peaks October 12-15. A sudden decrease in activity during the first months of 2025 could move the SC25 max to sometime between July and October 2024.

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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.