Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 12, 2015 at 04:50 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 11. Solar wind speed at SOHO ranged between 388 and 580 km/s under the influence of a high speed stream from CH649.

Solar flux at 20h UTC on 2.8 GHz was 153.7 (decreasing 15.6 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 155.3. The Potsdam WDC planetary A index was 9 (STAR Ap - based on the mean of three hour interval ap indices: 8.9). Three hour interval K indices: 23222310 (planetary), 13233321 (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 11 active regions using 2K resolution (SN: 265) and 10 active regions using 1K resolution (SN: 185) SDO images on the visible solar disk.

Region 12255 [S14W54] decayed slowly and quietly.
Region 12257 [N06W53] has a magnetic delta in a central northern penumbra and could produce an M class flare.
Region 12258 [N16E12] decayed slowly and quietly.
Region 12259 [S16E30] was mostly quiet and stable.
Region 12260 [N08W19] developed as new flux emerged.
Region 12261 [S11E46] was quiet and stable.
Region 12262 [S02W30] developed slowly and quietly.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4134 [S18W06] was quiet and stable.
S4142 [S18W48] developed further and has a weak magnetic delta structure in a northern penumbra.
New region S4143 [S16E07] emerged with penumbra spots.
New region S4144 [N10W43] emerged with a penumbra spot.

C2+ flares (GOES):

Magnitude Peak time (UTC) Location AR Comment
C3.3 (LDE) 02:53   12257  
C4.2 05:43   12257  
C3.4 (LDE) 09:24 N08W44 12257  

Coronal mass ejections (CMEs)

January 8-10: No obviously Earth directed CMEs were observed in 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 northern hemisphere coronal hole could rotate into an Earth facing position on January 14.

Propagation

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

Forecast

The geomagnetic field is expected to be mostly quiet on January 12-14.

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 18 4 2 S15W55 0130 EAO CRO apparently SWPC failed to recognize AR S4142 as a separate region
12257 2015.01.03
2015.01.06
24 29 17 N07W55 0450 EKC EAC

beta-gamma-delta

location: N06W53

12258 2015.01.06 3 8 2 N16E12 0010 BXO BXO  
12259 2015.01.06
2015.01.08
8 41 26 S16E26 0310 EKO EKO beta-gamma

area: 0440

location: S16E30

S4133 2015.01.07       N12W35         plage
S4134 2015.01.07   7 4 S18W06 0020   AXX images/AR_S4134_20150111_2345.png images/AR_S4134_20150110_2345.png  
12260 2015.01.08
2015.01.09
4 21 13 N09W17 0030 CRO DRI beta-gamma

area: 0070

location: N08W19

12261 2015.01.08
2015.01.09
2 3 1 S11E45 0030 HSX HSX  
S4137 2015.01.09       N06W42           plage
S4138 2015.01.09       S26W36           plage
12262 2015.01.10 4 20 10 S01W31 0020 CRO DRI beta-gamma
S4141 2015.01.10       S01E09         plage
S4142 2015.01.10   18 8 S18W48 0150   DAC beta-delta
S4143 2015.01.11   3 2 S16E07 0010   BXO    
S4144 2015.01.11   1   N10W43 0003   AXX  

 

Total spot count: 63 155 85  
Sunspot number: 133 265 185  (total spot count + 10 * number of spotted regions)
Weighted SN: 99 189 119  (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): 80 93 102 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
2015.01 147.8 (1)   40.7 (2A) / 114.8 (2B) / 88.8 (2C) (66.5 projected, -1.2) (12.8)

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.