Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 11, 2015 at 04:45 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 10. Solar wind speed at SOHO ranged between 364 and 466 km/s under the influence of a high speed stream from CH649.

Solar flux at 20h UTC on 2.8 GHz was 151.9 (decreasing 14.5 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 154.9. The Potsdam WDC planetary A index was 8 (STAR Ap - based on the mean of three hour interval ap indices: 7.9). Three hour interval K indices: 23222310 (planetary), 13233321 (Boulder).

The background x-ray flux is at the class B8 level.

At the time of counting spots (see image time), spots were observed in 11 active regions using 2K resolution (SN: 242) and 11 active regions using 1K resolution (SN: 175) SDO images on the visible solar disk.

Region 12255 [S14W42] decayed slowly and quietly.
Region 12257 [N05W41] has a weak magnetic delta in a central northern penumbra. Otherwise the region has decayed quickly losing spots and penumbral area. There's a slight chance of a minor M class flare.
Region 12258 [N15E24] decayed slowly and quietly losing rudimentary penumbra on both polarities.
Region 12259 [S16E43] was mostly quiet and stable.
Region 12260 [N09E01] decayed slowly and quietly.
Region 12261 [S10E58] was quiet and stable.
New region 12262 [S00W18] emerged with a few spots.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4133 [N12W22] was quiet and stable.
S4134 [S14W03] was quiet and stable.
New region S4141 [S01E22] was observed with penumbra spots.
New region S4142 [S18W34] emerged quickly near AR 12255. If the region develops further C and minor M class flares will become possible.

C2+ flares (GOES):

Magnitude Peak time (UTC) Location AR Comment
C2.1 01:53 N06W27 12257  
C3.3 11:33 N05W33 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 recurrent trans equatorial coronal hole (CH649) was in an Earth facing position on January 6-8.

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 quiet to unsettled on January 11 due to effects from CH649 and quiet on January 12-13.

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
12253 2014.12.29
2014.12.30
1     S06W85 0010 AXX     plage
12255 2015.01.01 6 5 3 S16W44 0070 DAO HAX  
S4124 2015.01.02       N04W55           plage
12257 2015.01.03
2015.01.06
35 41 23 N07W42 0470 EKC DAC

beta-gamma-delta

location: N05W41

12258 2015.01.06 4 17 7 N14E25 0020 CRO BXO  
12259 2015.01.06
2015.01.08
9 22 10 S18E38 0290 EKO EKO area: 0420

location: S16E43

S4133 2015.01.07   2 1 N12W22 0006   AXX  
S4134 2015.01.07   9 4 S14W03 0030   AXX images/AR_S4134_20150110_2345.png images/AR_S4134_20150109_2345.png  
12260 2015.01.08
2015.01.09
7 6 4 N09E01 0030 CRO CRO  
12261 2015.01.08
2015.01.09
1 2 1 S11E57 0030 HSX HAX  
S4137 2015.01.09       N06W29         plage
S4138 2015.01.09       S26W23         plage
12262 2015.01.10 3 13 4 S00W18 0020 CRO DRO    
S4141 2015.01.10   2 1 S01E22 0005   AXX    
S4142 2015.01.10   13 7 S18W34 0090   DRI  

beta-delta

Total spot count: 66 132 65  
Sunspot number: 146 242 175  (total spot count + 10 * number of spotted regions)
Weighted SN: 105 166 99  (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): 88 85 96 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
2015.01 147.2 (1)   36.5 (2A) / 113.0 (2B) / 88.0 (2C) (66.5 projected, -1.2) (13.2)

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.