Solar Terrestrial Activity Report

Activity chart

Last major update issued on February 9, 2026 at 07:05 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 2, 2026)
Solar cycle Solar cycles 23-25 (February 1, 2026) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24-25 progress (February 1, 2026) 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, 2026) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 12-14, 16, 24-25 (February 1, 2026) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs. solar cycles (December 21, 2025) Cycle 25 initial spots (final update December 25, 2019)
  Solar cycles 24-25 transition using 365d smoothing  

Recent activity

The geomagnetic field was at quiet to unsettled levels on February 8 due to effects associated with CH1342 during most of the first half of the day. A weak disturbance was observed beginning after 10h UT, possibly the transition to effects associated with CH1343/CH1344. Solar wind speed at SOHO ranged between 381 and 619 km/sec, averaging 450 km/sec (-36 km/sec compared to the previous day). The high latitude magnetometer at Andenes was at quiet to active 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 167.4 - increasing 54.5 over the previous solar rotation.

The 365 day average solar flux at 1 AU was 150.22 (183 days ago). The 81 day average solar flux at 1 AU was 148.2 (41 days ago, this is 50.1% of the total SC25 solar flux range from the max 81 day average peak on September 4, 2024 at 227.3 and an average 81 day flux of 69 at solar minimum). SC25 365d peak: 195.9 on October 13, 2024.

The Potsdam WDC planetary A index was 7 (STAR Ap - based on the average of three hour interval ap indices: 6.8). Three hour interval K indices: 32111113 (planetary), 12121222 (Boulder), 43110234 (Andenes).

The background x-ray flux is at the class C2 level (GOES 19).

At the time of counting spots (see image time), spots were observed in 13 active regions using 2K resolution (SN: 267) and in 11 active regions using 1K resolution (SN: 186) SDO/HMI images.

AR 14362 [S18W58] decayed slowly and was mostly quiet.
AR 14363 [S26W59] developed slowly and quietly.
AR 14366 [N14W58] displayed penumbral fragmentation and decay in the trailing spot section. The magnetic delta configuration weakened slightly. The region was very active producing many C and M flares.
AR 14367 [N08W30] decayed slowly and quietly.
AR 14368 [S09W27] was quiet and stable.
AR 14369 [S03W23] was quiet and stable.
AR 14370 [S18W16] was quiet and stable.
AR 14371 [S22W07] decayed slowly and was mostly quiet.
AR 14373 [N08E38] decayed slowly and quietly.

Spotted regions not observed (or interpreted differently) by SWPC/USAF:
AR S11835 [N11W15] was quiet and stable.
AR S11838 [S13E44] was quiet and stable.
New AR S11839 [N11E81] rotated into view with  large, mature spot.
New AR S11840 [S31W11] emerged with a tiny spot.

C2+ flares

Magnitude Peak time (UT) Location Source Recorded by Comment
C3.5 00:16   14366 GOES18  
C3.3 00:28   14371 GOES18  
C3.5 00:49   14366 GOES18  
C2.8 01:12   14366 GOES18  
C3.1 01:24   14366 GOES18  
C2.5 01:39   14366 GOES18  
C2.2 02:48   14366 GOES18  
C4.8 04:56   14366 GOES18  
C3.5 05:26   14366 GOES18  
C5.2 06:00   14369 GOES18 simultaneous flare in AR 14366
C5.1 06:13   14366 GOES18  
C4.0 06:56   14366 GOES18  
C6.1 07:46 N14W46 14366 GOES18  
C4.0 08:25   14366 GOES18  
C2.7 09:29   14366 GOES18  
C3.3 10:20   14366 GOES18  
C3.4 10:53   14366 GOES18  
M1.8 11:18 N18W48 14366 GOES18  
C6.2 11:33 behind northwest limb 14358 GOES18  
M1.7 11:43   14366 GOES18  
C7.6 12:30   14366 GOES18  
C5.7 12:52   14366 GOES18  
C3.8 13:35   14366 GOES18  
M2.7 13:53   14366 GOES18  
C5.5 14:25   14366 GOES18  
C4.3 14:59   14366 GOES18  
C4.4 15:04   14366 GOES18  
C5.6/1N 15:20 N14W50 14366 GOES18  
C4.7 15:27   14366 GOES18  
C4.0 15:35   14366 GOES18  
C4.4 16:01   14366 GOES18  
C3.3 17:03 S18W57 14362 GOES18  
C8.6/2N 17:38   14362 GOES18 simultaneous flare in AR 14366
C4.6 19:00   14362 GOES18  
C2.6 22:58   14362 GOES18  
C2.7 23:29   14362 GOES18  
C5.7 23:43   14366 GOES18  
C7.4 23:54   14366 GOES18  

Coronal mass ejections (CMEs)

February 6-8: No obviously Earth directed CMEs were observed in available coronagraph 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 negative polarity coronal hole (CH1343) rotated across the central meridian on February 5-8. A recurrent trans equatorial negative polarity coronal hole (CH1344) was Earth facing on February 6.

Forecast

The geomagnetic field is expected to be at quiet to active levels on February 9-10 due to effects associated with CH1343 and CH1344 and quiet to unsettled on February 11.

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
14362 2026.01.28 4 4 3 S18W60 0040 CAO CRO

was AR S11822

AREA: 0020

location: S18W58

14363 2026.01.28
2026.01.29
2 4 2 S26W62 0010 BXO CRO was AR S11823

location: S26W59

14366 2026.01.29
2026.01.30
20 51 32 N14W59 1000 FKC FKC beta-delta-gamma

was AR S11825

area: 1520

location: N14W57

14367 2026.01.31
2026.01.31
1 14 6 N09W31 0020 HAX CAO

was AR S11827

area: 0040

location: N08W30

14368 2026.01.31
2026.01.31
1 9 5 S10W28 0100 HSX CSO was AR S11828

area: 0180

location: S09W27

14369 2026.01.31
2026.02.01
1 7 3 S03W23 0110 HSX CSO was AR S11829

area: 0180

14370 2026.02.01
2026.02.02
  5 1 S18W17 0010   BXO was AR S11830

location: S18W16

14371 2026.02.01
2026.02.02
4 17 12 S23W06 0060 CAO CAO

was AR S11831

area: 0080

location: S23W07

S11833 2026.02.03       S29W33            
S11835 2026.02.03   2 1 N11W15 0004   BXO  
14373 2026.02.05
2026.02.06
5 21 10 N08E43 0130 CSO DSO

was AR S11836

area: 0220

location: N08E38

S11837 2026.02.07       S12E13          
S11838 2026.02.07   1   S13E44 0001   AXX  
S11839 2026.02.08   1 1 N11E81 0320   HHX    
S11840 2026.02.08   1   S31W11 0001   AXX    
Total spot count: 38 137 76  
Sunspot number: 118 267 186  (total spot count + 10 * number of spotted regions)
Weighted SN: 78 188 127  (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): 130 147 149  

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number (4) Average ap
(3)
Measured 1 AU
2024.05 187.7 191.9 172.1 149.1 (+4.6) 23.56
(SC25 peak)
2024.08  246.1
(SC25 peak)
252.2 216.0  (SC25 peak) 156.8 (+1.8) 15.96
2024.10 221.0 219.6 165.8 160.9 (+1.5) (SC25 solar max) 18.99
2024.11 199.6 195.3 154.1 157.2 (-3.7) 9.33
2024.12 197.3 191.2 154.6 151.2 (-6.0) 8.42
2025.01 190.3 184.2 137.0 146.2 (-5.0) 13.17
2025.02  184.2 179.7 155.7 139.8 (-6.4) 14.42
2025.03 163.7 162.1 134.2 135.9 (-3.9) 15.96
2025.04 162.5 163.6 141.4 133.3 (-2.6) 17.62
2025.05  135.3 138.3 78.5 128.6 (-4.7) 17.26
2025.06 131.3 135.4 114.6 124.7 (-3.9) 21.43
2025.07 137.8 142.3 125.9 122.4 (-2.3) 11.80
2025.08 154.9 158.7 133.7 (119.9 projected, -2.5) 9.97
2025.09 154.4 156.0 129.7 (117.2 projected, -2.7) 14.02
2025.10 139.5 138.6 114.6 (114.1 projected, -3.1) 15.64
2025.11 140.3 137.3 91.7 (112.4 projected, -1.7) 21.01
2025.12 160.8 155.8 124.0 (111.1 projected, -1.3) 13.35
2026.01 149.4 144.0 112.6 (107.2 projected, -3.9) 23.2
2026.02 169.6 (1)   38.6 (2A) / 135.3 (2B) / 149.7 (2C) (103.0 projected, -4.2) (10.0)
2026.03       (98.4 projected, -4.6)  
2026.04       (94.5 projected, -3.9)  
2026.05       (93.3 projected, -1.2)  
2026.06       (91.1 projected, -2.2)  
2026.07       (86.7 projected, -4.4)  

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 October 2025

Sunspot activity was on a decreasing trend from September 2024 until mid August 2025 (using the average solar flux over 3 solar rotations as a proxy). Then a strong surge in activity saw solar flux peak in late August 2025 just below the largest peaks seen in 2024. A slow decrease in activity from the August level has been observed in September and October 2025.

All 365 day smoothed sunspot numbers reached a maximum on October 11-12, 2024
. This became the peak of SC25 (365 day smoothed peaks: STAR 1K: 236.1, STAR 2K: 364.3, NOAA SN: 156.0, ISN: 163.9), while the 365d smoothed solar flux peaked on October 13, 2024, just 1.7% below the SC23 peak, and 62.6% above the SC24 peak.

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This report has been prepared by Jan Alvestad. It is based on the analysis of data from whichever 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.