Solar Terrestrial Activity Report

Activity chart

Last major update issued on January 14, 2015 at 05:10 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 on January 13. Solar wind speed at SOHO ranged between 361 and 444 km/s.

Solar flux at 20h UTC on 2.8 GHz was 148 (decreasing 50.5 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: 6.3). Three hour interval K indices: 12112222 (planetary), 11113332 (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: 211) and 9 active regions using 1K resolution (SN: 137) SDO images on the visible solar disk.

Region 12257 [N07W80] rotated to the northwest limb producing 2 M class flares.
Region 12258 [N15W17] was quiet and stable.
Region 12259 [S16E05] decayed slowly and quietly.
Region 12260 [N08W47] was quiet and stable.
Region 12261 [S11E19] was quiet and stable.
Region 12262 [S02W55] decayed slowly and quietly.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4134 [S20W21] was quiet and stable.
S4142 [S18W75] decayed slowly and quietly.
S4143 [S09W32] reemerged with a few spots.
S4145 [N09E21] was quiet and stable.
S4146 [N32E13] was quiet and stable.

C2+ flares (GOES):

Magnitude Peak time (UTC) Location AR Comment
M5.6/2B 04:24 N06W70 12257  
M4.9 04:58   12257  
C2.4 13:14 N04W79 12257  

Coronal mass ejections (CMEs)

January 11-13: 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 northern hemisphere coronal hole (CH650) 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 to fair. Propagation on long distance northeast-southwest paths is poor.

Forecast

The geomagnetic field is expected to be mostly quiet on January 14-16.

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 7     S16W80 0110 DAO     spotless
12257 2015.01.03
2015.01.06
6 6 3 N07W81 0240 EAC DAO

 

12258 2015.01.06   6 1 N16W16 0016   BXO  
12259 2015.01.06
2015.01.08
10 33 22 S15W01 0360 EKO EAO beta-gamma

location: S16E05

S4134 2015.01.07   7 2 S20W21 0010   AXX images/AR_S4134_20150112_2345.png  
12260 2015.01.08
2015.01.09
4 17 7 N09W47 0060 DAO DAI  
12261 2015.01.08
2015.01.09
1 3 1 S11E17 0030 HAX CAO  
12262 2015.01.10 5 9 2 N01W56 0040 CSO CRO

location: S02W55

S4141 2015.01.10       S01W17           plage
S4142 2015.01.10   8 5 S18W75 0060   DAO  
S4143 2015.01.11   7 4 S09W32     CRO    
S4145 2015.01.12   1   N09E21 0001   AXX  
S4146 2015.01.12   4   N32E13 0006   AXX  
S4147 2015.01.12       S30E17        

plage

Total spot count: 33 101 47  
Sunspot number: 93 211 137  (total spot count + 10 * number of spotted regions)
Weighted SN: 68 132 78  (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): 56 74 75 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
2015.01 148.6 (1)   47.3 (2A) / 112.8 (2B) / 87.4 (2C) (66.5 projected, -1.2) (11.8)

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.