Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 15, 2015 at 04:55 UTC.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 23-24 (last update January 1, 2015)] [Cycle 24 progress (last update January 1, 2015) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update January 1, 2015)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update January 1, 2015)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update January 3, 2015)]

[Noon SDO sunspot count 1K Reference: 4K (large file) (updated daily)]

[POES auroral activity level October 2009 - December 2012]
[Solar polar fields vs solar cycles - updated December 27, 2014]
[Presentations: 3rd SSN Workshop, Tucson, 2013 (pdf) / 4th SSN Workshop, Locarno, 2014]

Recent activity

The geomagnetic field was quiet to unsettled on January 14. Solar wind speed at SOHO ranged between 355 and 431 km/s.

Solar flux at 20h UTC on 2.8 GHz was 141.8 (decreasing 71.5 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 155.8. The Potsdam WDC planetary A index was 6 (STAR Ap - based on the mean of three hour interval ap indices: 5.5). Three hour interval K indices: 20123121 (planetary), 20233311 (Boulder).

The background x-ray flux is at the class C1 level.

At the time of counting spots (see image time), spots were observed in 12 active regions using 2K resolution (SN: 199) and 9 active regions using 1K resolution (SN: 133) SDO images on the visible solar disk.

Region 12258 [N14W32] decayed slowly and quietly.
Region 12259 [S16W08] developed as new flux emerged to the south of the main penumbrae. There's polarity intermixing and a minor M class flare is possible.
Region 12260 [N08W61] decayed slowly and quietly.
Region 12261 [S11E07] was quiet and stable.
Region 12262 [S02W68] decayed slowly and quietly.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4134 [S24W32] was quiet and stable.
S4143 [S09W45] decayed slowly and quietly.
S4146 [N36E09] gained trailing penumbra spots.
New region S4148 [S13E52] emerged with penumbra spots.
New region S4149 [S06E70] emerged with penumbra spots.
New region S4150 [N09E76] rotated into view with penumbra spots.
New region S4151 [N23E64] emerged with a penumbra spot.

C2+ flares (GOES):

Magnitude Peak time (UTC) Location AR Comment
C4.7 02:33   12257  
C9.7 03:47   12257  
C7.7 04:56   12257  
C2.3 06:51 S14W02 12259  
C2.6 08:45 N07W86 12257  
C5.3 09:43   12257  
M2.2 12:58   12257  
C2.3 18:26   12259  

Coronal mass ejections (CMEs)

January 12-14: No obviously Earth directed CMEs were observed in LASCO imagery. A CME associated with a C3 flare in AR 12261 on January 12 may have had weak Earth directed components.

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 trans equatorial coronal hole (CH650) was in an Earth facing position on January 14-15.

Propagation

Long distance low and medium frequency (below 2 MHz) propagation along paths north of due west over upper middle latitudes is poor to fair. Propagation on long distance northeast-southwest paths is poor to fair.

Forecast

The geomagnetic field is expected to be mostly quiet on January 15-16 with a minor chance of a weak CME impact on January 15. A high speed stream from CH650 could cause unsettled and active intervals on Janaury 17-18.

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) 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 numbered solar regions according to the Solar Region Summary provided by NOAA/SWPC. 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.

Active region Date numbered
detected
Spot count Location at midnight Area Classification SDO / HMI 4K continuum
image with magnetic polarity overlay
Comment
SWPC Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
12255 2015.01.01 3     S16W89 0080 CAO       spotless, rotated out of view
12257 2015.01.03
2015.01.06
3     N07W93 0120 DAO    

rotated out of view

12258 2015.01.06   4   N16W30 0010   BXO  
12259 2015.01.06
2015.01.08
15 38 25 S15W13 0260 EKC EAI beta-gamma

location: S16W08

S4134 2015.01.07   3 1 S24W32 0008   AXX  
12260 2015.01.08
2015.01.09
6 5 3 N10W59 0070 CAO DAO  
12261 2015.01.08
2015.01.09
1 8 7 S11E04 0030 HSX CAO  
12262 2015.01.10 1 2 1 S01W68 0010 AXX AXX

area: 0004

S4141 2015.01.10       S01W30           plage
S4143 2015.01.11   7 1 S09W45 0010   BXO  
S4145 2015.01.12       N09E08         plage
S4146 2015.01.12   3 2 N36E09 0010   BXO  
S4147 2015.01.12       S30E04           plage
S4148 2015.01.14   3   S13E52          
S4149 2015.01.14   3 2 S06E70 0010   BXO    
S4150 2015.01.14   2 1 N09E76 0006   AXX    
S4151 2015.01.14   1   N23E64 0002   AXX  

 

Total spot count: 29 79 43  
Sunspot number: 89 199 133  (total spot count + 10 * number of spotted regions)
Weighted SN: 59 94 58  (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): 53 70 73 k * (sunspot number). k = 0.6 for SWPC, k = 0.35 for MSN 2K, k = 0.55 for MSN 1K (MSN=Magnetic Sunspot Number)

Monthly solar cycle data

Month Average solar flux International sunspot number
(WDC-SILSO)
Smoothed sunspot number Average ap
(3)
Measured 1 AU
2013.09 102.6 103.7 36.9 73.1 (+4.1) 5.23
2013.10  132.1 131.2 85.6 75.0 (+1.9) 7.71
2013.11  148.3 145.1 77.6 75.4 (+0.4) 5.68
2013.12 147.7 143.1 90.3 76.0 (+0.6) 4.68
2014.01 157.4 152.4 81.8 77.3 (+1.3) 5.44
2014.02 170.3
(cycle peak)
166.3 102.3 (cycle peak) 78.4 (+1.1) 10.70
2014.03 149.9 148.5 91.9 80.8 (+2.4) 4.88
2014.04 143.9 144.8 84.7 81.9 (+1.1)
(likely solar max)
7.88
2014.05 129.7 132.9 75.2 80.5 (-1.4) 5.75
2014.06 122.0 125.8 71.0 79.7 (-0.8) 6.72
2014.07 137.4 141.8 72.5 (78.6 projected, -1.1) 4.50
2014.08 124.7 127.9 74.7 (76.2 projected, -2.4) 7.71
2014.09 146.6 148.1 87.6 (73.0 projected, -3.2) 9.78
2014.10 153.4 152.9 60.6 (70.5 projected, -2.5) 8.96
2014.11 154.8 151.4 70.1 (68.8 projected, -1.7) 9.33
2014.12 158.7 153.8 78.0 (67.7 projected, -1.1) 11.24
2015.01 148.2 (1)   50.2 (2A) / 111.1 (2B) / 86.0 (2C) (66.5 projected, -1.2) (11.3)

1) Running average based on the daily 20:00 UTC observed solar flux value at 2800 MHz.
2A) Current impact on the monthly sunspot number based on the Boulder (NOAA/SWPC) sunspot number (accumulated daily sunspots / month days). The official WDC-SILSO international sunspot number is typically 30-50% lower. 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.

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 the UTC day. Comments and suggestions are always welcome.

SDO images are courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.