Solar Terrestrial Activity Report

Activity chart

Last major update issued on October 23, 2014 at 05:50 UTC. Updates will be irregular until October 27.

[Solar and geomagnetic data - last month (updated daily)]
[Solar wind and electron fluence charts (updated daily)]
[Solar cycles 23-24 (last update October 1, 2014)] [Cycle 24 progress (last update October 1, 2014) ]
[Solar cycles 1-20]
[Graphical comparison of cycles 21, 22, 23 and 24 (last update October 1, 2014)]
[Graphical comparison of cycles 10, 12, 13, 14, 16 and 24 (last update October 1, 2014)]
[Historical solar and geomagnetic data charts 1954-2006 (last update April 5, 2007)]
[Archived reports since January 2003 (last update October 10, 2014)]

[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 October 11, 2014]
[Presentations: 3rd SSN Workshop, Tucson, 2013 (pdf) / 4th SSN Workshop, Locarno, 2014]

Recent activity

The geomagnetic field was quiet to active on October 22. Solar wind speed at SOHO ranged between 450 and 563 km/s under the influence of a high speed stream from CH640.

Solar flux at 20h UTC on 2.8 GHz was 216 (increasing 58 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 138.5. The Potsdam WDC planetary A index was 12 (STAR Ap - based on the mean of three hour interval ap indices: 11.5). Three hour interval K indices: 43222322 (planetary), 33334321 (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 9 active regions using 2K resolution (SN: 296) and 8 active regions using 1K resolution (SN: 189) SDO images on the visible solar disk.

Region 12187 [S09W68] was quiet and stable.
Region 12192 [S14E09] continued to gain spots and area. Some penumbral area in the central southern parts disappeared after the X class event. Multiple magnetic delta structures can be observed within the manin penumbral area. Further major flares are possible.
Region 12193 [N04W32] was quiet and mostly stable.
Region 12194 [S12E46] decayed slowly and quietly.
New region 12195 [N08E73] rotated partly into view on October 21 and was numbered the next day by SWPC.

Spotted regions not numbered (or interpreted differently) by SWPC:
S3921 [N14W07] was quiet and stable.
S3925 [S25W23] reemerged with a penumbra spot.
New region S3930 [N08E42] was observed with penumbra spots.
New region S3931 [N13E00] emerged with penumbra spots.

An interesting region just behind the southeast limb displayed significant activity and is obviously capable of producing M class flares.

C2+ flares (GOES):

Magnitude Peak time (UTC) Location AR Comment
M8.7 (LDE) 01:59   12192  
M2.7 05:17   12192  
C4.6 09:12   12193  
C3.2 12:05   12192  
X1.6/2B (LDE) 14:28 S14E13 12192  
M1.4 15:57 SE limb    
C5.7 16:59   12192  
C9.8 (LDE) 17:50   12192  
C6.5 21:16 SE limb    

Coronal mass ejections (CMEs)

October 20-22: No obviously Earth directed CMEs were observed in LASCO and STEREO 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 (CH640) was in an Earth facing position on October 19-22.

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 fair.

Forecast

The geomagnetic field is expected to be quiet to unsettled on October 23-25 due to effects from CH640.

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
12187 2014.10.11 2 6 2 S10W67 0110 CSO CKO area: 0290

location: S09W68

S3900 2014.10.13       N03W44           plage
12191 2014.10.14
2014.10.15
      S11W52         plage
12190 2014.10.14       N22W51           plage
S3910 2014.10.16       S17W32           plage
12192 2014.10.16
2014.10.17
55 157 83 S12E06 2700 FKC FKC beta-gamma-delta

location: S14E09

area: 3800

S3914 2014.10.16       N05W26           plage
S3915 2014.10.17       S24W34           plage
S3916 2014.10.17       S25W47           plage
12193 2014.10.18
2014.10.19
11 22 14 N05W31 0120 DAO DAI area: 0180
S3921 2014.10.19   2 1 N14W07 0006   BXO  
12194 2014.10.19
2014.10.21
2 5 3 S11E47 0130 CSO CSO area: 0160
S3925 2014.10.21   1 1 S25W23 0003   AXX    
12195 2014.10.21
2014.10.22
3 6 4 N08E70 0060 DSO DAO area: 0110
S3928 2014.10.21       S08W39         plage
S3930 2014.10.22   5   N08E42 0006   BXO    
S3931 2014.10.22   2 1 N13E00 0005   AXX    
Total spot count: 73 206 109  
Sunspot number: 123 296 189  (total spot count + 10 * number of spotted regions)
Weighted SN: 103 241 144  (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): 74 104 104 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
2013.06 110.1 113.7 52.5 62.6 (+2.7) 12.60
2013.07 115.5 119.3 57.0 65.5 (+2.9) 9.47
2013.08 114.6 118.3 66.0 69.0 (+3.5) 8.27
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 (82.7 projected, +1.9) 7.88
2014.05 129.7 132.9 75.2 (82.3 projected, -0.4) 5.75
2014.06 122.0 125.8 71.0 (81.1 projected, -1.2) 6.72
2014.07 137.4 141.8 72.5 (79.4 projected, -1.7) 4.50
2014.08 124.7 127.9 74.7 (77.1 projected, -2.3) 7.71
2014.09 146.2   87.6 (73.8 projected, -3.3) 9.78
2014.10 141.3 (1)   58.8 (2A) / 82.9 (2B) / 86.0 (2C) (71.4 projected, -2.4) (8.6)

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.