The geomagnetic field was quiet on January 11, weakly under the influence of effects associated with CH1196. Solar wind speed at SOHO ranged between 408 and 524 km/sec. The high latitude magnetometer at Andenes recorded quiet to unsettled levels.
Solar flux density measured at 20h UT on 2.8 GHz was 192.5 - increasing 48.2 over the previous solar rotation. (Centered 1 year average SF at 1 AU - 183 days ago: 158.24. In comparison SC24 peaked on June 28, 2014 at 145.50. Current SC25 peak: 158.71 on June 27, 2023). The Potsdam WDC planetary A index was 5 (STAR Ap - based on the mean of three hour interval ap indices: 5.4). Three hour interval K indices: 11222112 (planetary), 02233211 (Boulder), 22111103 (Andenes).
The background x-ray flux is at the class C2 level (GOES 16).
At the time of counting spots (see image time), spots were observed in 16 active regions using 2K resolution (SN: 381) and in 14 active regions using 1K resolution (SN: 246) SDO/HMI images.
Region 13539 [N10W53] decayed in the leading
spot section while development was observed in the trailing spots where a
magnetic delta structure formed.
Region 13540 [S17W09] was mostly quiet and stable.
Region 13541 [S20W10] displayed no major changes and was mostly quiet.
Region 13543 [S07W76] decayed slowly and quietly.
Region 13544 [N18E04] was quiet and stable.
Region 13545 [S05E41] was quiet and stable.
Region 13546 [S24E25] has weak polarity intermixing and was mostly
quiet.
New region 13547 [N19E18] emerged on January 10 with SWPC numbering
the region the following day. Several C flares were observed.
Spotted regions not observed (or interpreted
differently) by SWPC/USAF:
S9279 [N09W67] decayed and had only tiny spots by the end of the day
S9303 [S12E08] was quiet and stable.
S9310 [N06W17] was quiet and stable.
S9313 [S22W01] decayed slowly and quietly.
S9315 [N25E65] was quiet and stable.
S9316 [N11E56] developed slowly and produced several C flares. The
region appears to be developed a magnetic delta structure.
S9317 [S20E73] rotated fully into view and was mostly quiet.
New region S9318 [S10W32] emerged with a tiny spot.
C2+ flares:
| Magnitude | Peak time (UT) | Location | Source | Recorded by | Comment |
| C4.6 | 00:05 | 13539 | GOES16 | simultaneous flares in ARs 13538 and S9317 | |
| C4.3 | 00:54 | S9317 | GOES16 | simultaneous flare in AR S9315 | |
| C5.2 | 01:12 | 13539 | GOES16 | simultaneous flare in AR S9317 | |
| C3.5 | 01:39 | 13538 | GOES16 | ||
| C4.2 | 02:21 | 13538 | GOES16 | ||
| C3.4 | 03:14 | 13538 | GOES16 | ||
| C3.9 | 03:27 | 13538 | GOES16 | ||
| C4.5 | 03:33 | 13539 | GOES16 | ||
| C4.6 | 03:43 | S25E35 | 13546 | GOES16 | |
| C3.1 | 04:15 | N09W46 | 13539 | GOES16 | |
| C2.2 | 04:54 | 13546 | GOES16 | ||
| C2.6 | 05:43 | 13546 | GOES16 | ||
| C3.0 | 06:05 | 13541 | GOES16 | simultaneous flare in AR 13538 | |
| C7.8 | 06:19 | N13W47 | 13539 | GOES16 | |
| C4.3 | 06:33 | 13538 | GOES16 | ||
| C4.1 | 06:38 | 13538 | GOES16 | ||
| C3.0 | 08:03 | 13541 | GOES16 | ||
| C4.1 | 08:19 | S9316 | GOES16 | incorrectly attributed to AR 13540 by SWPC | |
| C6.4 | 09:01 | N09W52 | 13539 | GOES16 | simultaneous flare in AR 13538 |
| C4.5 | 09:25 | 13539 | GOES16 | ||
| C3.0 | 10:09 | 13539 | GOES16 | ||
| C3.9 | 10:42 | 13538 | GOES16 | ||
| C4.2 | 11:34 | 13538 | GOES16 | ||
| C3.2 | 11:51 | 13539 | GOES16 | simultaneous flare in AR 13538 | |
| C9.4 | 12:09 | 13538 | GOES16 | ||
| M1.3 | 12:51 | 13538 | GOES16 | ||
| C4.6 | 13:05 | 13538 | GOES16 | ||
| C3.7 | 13:46 | 13539 | GOES16 | ||
| C2.5 | 14:57 | 13547 | GOES16 | ||
| C3.0 | 15:21 | 13539 | GOES16 | ||
| C2.9 | 15:42 | 13547 | GOES16 | ||
| C3.6 | 16:11 | 13538 | GOES16 | ||
| C6.4 | 16:32 | 13538 | GOES16 | ||
| C8.3 | 16:46 | 13538 | GOES16 | ||
| C2.8 | 17:31 | 13547 | GOES16 | ||
| C2.6 | 17:42 | 13547 | GOES16 | ||
| M1.5 | 17:52 | 13539 | GOES16 | ||
| C3.3 | 19:04 | S9316 | GOES16 | ||
| M1.2 | 19:23 | 13538 | GOES16 | ||
| C7.8 | 20:30 | 13539 | GOES16 | ||
| C2.6 | 21:07 | 13547 | GOES16 | ||
| C3.6 | 22:54 | N09W60 | 13539 | GOES16 | |
| C4.6 | 23:11 | S9316 | GOES16 | simultaneous flares in ARs 13543 and 13539 | |
| C3.4 | 23:41 | S9316 | GOES16 |
January 10-11: No obviously Earth directed CME observed.
January 9: A partial halo CME was observed after a large filament
eruption in the southeast quadrant. A weak shock from this CME is possible
on January 12 or 13.
[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 positive polarity northern hemisphere coronal hole (CH1197) will likely rotate across the central meridian on January 13.
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.
The geomagnetic field is expected to be quiet on January 12. Quiet to active conditions are possible on January 12-14 due to to CME effects.
| 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.
(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 | ||||||||||
| 13536 | 2023.12.31 2023.12.31 |
1 | N07W72 | 0010 | AXX |
 |
location: N05W76 spotless |
||||
| S9279 | 2023.12.31 | 2 | N09W67 | 0005 | BXO |
 |
 |
||||
| 13537 | 2024.01.01 2024.01.02 |
N18W66 |
 |
location: N17W71 |
|||||||
| S9291 | 2024.01.03 | N15W33 |
 |
||||||||
| S9293 | 2024.01.04 | N27W27 | |||||||||
| 13541 | 2024.01.04 2024.01.05 |
15 | 30 | 14 | S22W04 | 0100 | ESI | DRI |
 |
 |
beta-gamma location: S20W10 SWPC data appears to include AR S9313 |
| 13540 | 2024.01.04 2024.01.05 |
12 | 23 | 8 | S18W10 | 0150 | CAO | CAO |
 |
 |
location: S17W09 |
| S9297 | 2024.01.04 | S07W22 |
 |
||||||||
| 13539 | 2024.01.05 | 13 | 36 | 18 | N10W56 | 0230 | DAI | DAC |
 |
 |
beta-delta location: N10W53 |
| 13542 | 2024.01.05 | N18W71 | this was the eastern part of AR 13537 | ||||||||
| S9299 | 2024.01.05 | N21W55 | |||||||||
| 13544 | 2024.01.05 2024.01.07 |
1 | 8 | 2 | N18E04 | 0010 | AXX | CRO |
 |
 |
area: 0020 |
| 13543 | 2024.01.06 2024.01.07 |
4 | 6 | 2 | S06W78 | 0050 | CSO | CRO |
 |
 |
location: S07W76 |
| S9303 | 2024.01.06 | 14 | 5 | S12E08 | 0020 | BXO |
 |
 |
|||
| S9304 | 2024.01.06 | N19W46 | |||||||||
| S9306 | 2024.01.07 | S15W47 | |||||||||
| 13545 | 2024.01.08 2024.01.09 |
1 | 8 | 5 | S06E40 | 0150 | HSX | CHO |
 |
 |
area: 0380 location: S05E41 |
| 13546 | 2024.01.08 2024.01.09 |
11 | 29 | 16 | S24E22 | 0070 | DAI | DRI |
 |
 |
beta-gamma area: 0160 location: S24E25 |
| S9310 | 2024.01.09 | N06W30 |
 |
||||||||
| S9311 | 2024.01.09 | N19E21 | |||||||||
| S9312 | 2024.01.09 | 10 | 3 | S16E36 | 0030 | DRO |
 |
 |
|||
| S9313 | 2024.01.09 | 22 | 13 | S22W01 | 0100 | DAO |
 |
 |
|||
| 13547 | 2024.01.10 2024.01.11 |
3 | 13 | 8 | N19E19 | 0040 | DSO | DAO |
 |
 |
beta-gamma location: N19E18 area: 0120 |
| S9315 | 2024.01.10 | 2 | 2 | N25E65 | 0015 | DRO |
 |
 |
|||
| S9316 | 2024.01.10 | 11 | 7 | N11E56 | 0060 | DRI |
 |
 |
beta-delta? | ||
| S9317 | 2024.01.10 | 6 | 3 | S20E73 | 0330 | DHO |
 |
 |
|||
| S9318 | 2024.01.11 | 1 | S10W32 | 0002 | AXX |
 |
|||||
| Total spot count: | 61 | 221 | 106 | ||||||||
| Sunspot number: | 151 | 381 | 246 | (total spot count + 10 * number of spotted regions) | |||||||
| Weighted SN: | 96 | 282 | 167 | (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): | 166 | 210 | 197 | ||||||||
| 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 |
| 2022.05 | 133.8 | 136.8 | 96.5 | 77.4 (+4.4) | 7.48 |
| 2022.06 | 116.1 | 119.8 | 70.3 | 81.1 (+3.7) | 8.20 |
| 2022.07 | 125.4 | 129.5 | 91.4 | 86.7 (+5.6) | 9.51 |
| 2022.08 | 114.2 | 117.1 | 74.6 | 92.6 (+5.9) | 10.92 |
| 2022.09 | 135.1 | 136.5 | 96.0 | 96.5 (+3.9) | 12.18 |
| 2022.10 | 133.5 | 132.7 | 95.5 | 98.9 (+2.4) | 11.16 |
| 2022.11 | 123.4 | 120.7 | 80.5 | 101.2 (+2.3) | 9.33 |
| 2022.12 | 147.9 | 143.4 | 112.8 | 106.7 (+5.5) | 10.99 |
| 2023.01 | 182.4 | 176.6 | 144.4 | 113.3 (+6.6) | 8.73 |
| 2023.02 | 167.2 | 163.2 | 111.3 | 117.8 (+3.5) | 14.48 (current SC25 peak) |
| 2023.03 | 157.2 | 155.6 | 123.3 | 121.0 (+3.2) | 14.42 |
| 2023.04 | 145.4 | 146.4 | 97.6 | 122.7 (+1.7) | 13.40 |
| 2023.05 | 155.6 | 159.2 | 137.4 | 123.9 (+1.2) | 10.67 |
| 2023.06 | 161.7 | 166.8 | 160.5 | 125.0 (+1.1) (SC25 solar max candidate) |
8.95 |
| 2023.07 | 176.4 | 182.2 | 159.1 | (124.6 projected, -0.4) | 8.15 |
| 2023.08 | 153.7 | 157.6 | 114.8 | (124.1 projected, -0.5) | 7.19 |
| 2023.09 | 154.4 | 156.0 | 133.6 | (123.8 projected, -0.3) | 14.26 |
| 2023.10 | 142.8 | 141.9 | 99.4 | (124.6 projected, +0.8) | 8.16 |
| 2023.11 | 153.5 | 150.2 | 105.4 | (124.6 projected, +0.0) | 12.20 |
| 2023.12 | 151.1 | 146.4 | 114.2 | (121.2 projected, -3.4) | 9.60 |
| 2024.01 | 161.3 (1) | 43.2 (2A) / 121.8 (2B) / 144.9 (2C) | (117.9 projected, -3.3) | (5.4) | |
| 2024.02 | (117.1 projected, -0.8) | ||||
| 2024.03 | (116.6 projected, -0.5) | ||||
| 2024.04 | (116.6 projected, +0.0) | ||||
| 2024.05 | (117.0 projected, -0.8) | ||||
| 2024.06 | (114.9 projected, -2.1) | ||||
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: WDC-SILSO, Royal Observatory
Of Belgium, Brussels
The relatively low solar activity during the last months of 2023 significantly increased the possibility that solar cycle 25 has already peaked. Whether the first peak in June 2023 will be the actual solar max will not be known for some time. Due to the relatively high solar activity early in 2023 it is unlikely there will be another solar max candidate, if at all, until at least May 2024. Both the northern and southern polar fields, as well as the averaged total field, have already reversed polarities.
--------------------------------------------------------------------------------------
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.
