Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 10, 2015 at 04:45 UT.

Charts (* = updated daily) Data and archive
  Solar wind (*) Solar and geomagnetic data - last month (*)
  Electron fluence (*) Archived daily reports and monthly data from 2003.01 (June 1, 2015)
Solar cycle Solar cycles 23-24 (June 1, 2015) Historical solar and geomagnetic data charts 1954-2006 (April 5, 2007)
  Cycle 24 progress (June 1, 2015) Noon SDO sunspot count 1K Reference: 4K (large file) (*)
  Solar cycles 1-20 POES auroral activity level October 2009 - December 2012
  Comparison of cycles 21, 22, 23 and 24 (June 1, 2015) 3rd SSN Workshop, Tucson, 2013
  Comparison of cycles 10, 12, 13, 14, 16 and 24 (June 1, 2015) 4th SSN Workshop, Locarno, 2014
  Solar polar fields vs solar cycles (June 8, 2015)  

Recent activity

The geomagnetic field was quiet to active on June 9 due to effects from CH671. Solar wind speed at SOHO ranged between 563 and 684 km/s.

Solar flux at 17h UTC on 2.8 GHz was 131.4 (decreasing 25.6 over the last solar rotation, the measurement at 20h UT was flare enhanced). The 90 day 10.7 flux at 1 AU was 125.5. The Potsdam WDC planetary A index was 14 (STAR Ap - based on the mean of three hour interval ap indices: 14.0). Three hour interval K indices: 43323332 (planetary), 43333*** (Boulder).

The background x-ray flux is at the class B5 level.

At the time of counting spots (see image time), spots were observed in 12 active regions using 2K resolution (SN: 243) and 8 active regions using 1K resolution (SN: 143) SDO images on the visible solar disk.

Region 12360 [N15W30] decayed slowly and simplified magnetically. C class flaring is possible.
Region 12361 [N19W02] decayed slowly and quietly.
Region 12362 [N07E03] was quiet and simplified magnetically.
Region 12364 [S05E24] decayed slowly producing a low level C flare. This is a reversed polarities region.
Region 12365 [S13E21] decayed slowly and quietly. The region has reversed polarities.
Region 12366 [N17E19] was quiet and stable.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4530 [N13E13] reemerged with penumbra spots.
S4531 [S07E32] lost the trailing spots and was quiet.
New region S4532 [N07E15] emerged with penumbra spots.
New region S4533 [S32E50] emerged with a penumbra spot.
New region S4534 [S22E00] was observed with a penumbra spot.
New region S4535 [S07E04] emerged with penubmra spots.

C2+ flares:

Magnitude Peak time (UTC) Location AR Recorded by Comment
C5.8 03:53   12360 GOES14  
C2.8/1F 20:01 S04E24 12364 GOES15 CME?

Flare activity according to SDO/EVE/ESP XRS-B proxy

Coronal mass ejections (CMEs)

June 7-9: No obviously Earth directed CMEs were observed. In limited imagery a CME was observed mostly off the east and northeast limb late on June 9. This may be associated with the C2 event in AR 12364.

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 (CH672) will likely rotate across the central meridian on June 10-11.

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 June 10 due to effects from CH671. Quiet conditions are likely on June 11-12. Effects from CH672 could cause quiet to active conditions on June 13-14.

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 overlays
Comment
SWPC Magnetic
(SDO)
SWPC STAR Current Previous
2K 1K
12358 2015.05.31       S03W51        

 

S4518 2015.06.01       S18W66            
12360 2015.06.01
2015.06.03
20 44 22 N15W31 0120 EAI EAI images/AR_12360_20150609_2345.png images/AR_12360_20150608_2345.png  
12361 2015.06.03
2015.06.04
5 21 10 N17W04 0040 CAO CRO images/AR_12361_20150608_2345.png location: N19W02
12362 2015.06.03
2015.06.04
11 26 15 N06W01 0100 DSO DSO

location: N07E03

12363 2015.06.04
2015.06.05
      N04W75            
S4526 2015.06.04       S12W14            
12365 2015.06.05
2015.06.06
6 4 2 S13E22 0060 CAO CAO area: 0110

reversed polarities

12364 2015.06.05
2015.06.06
3 4 4 S07E24 0010 AXX CRO

reversed polarities

location: S05E24

12366 2015.06.06
2015.06.07
5 13 8 N17E19 0020 CRO DRI  
S4530 2015.06.07   3 1 N13E13 0005   AXX    
S4531 2015.06.08   2   S07E32 0005   AXX  
S4532 2015.06.09   2 1 N07E15 0006   BXO    
S4533 2015.06.09   1   S32E50 0001   AXX    
S4534 2015.06.09   1   S22E00 0001   AXX    
S4535 2015.06.09   2   S07E04 0003   AXX    
Total spot count: 50 123 63  
Sunspot number: 110 243 143  (total spot count + 10 * number of spotted regions)
Weighted SN: 80 147 87  (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): 66 85 79 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
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) (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 78.5 (-1.2) 4.50
2014.08 124.7 127.9 74.7 75.5 (-3.0) 7.71
2014.09 146.6 148.1 87.6 70.8 (-4.7) 9.78
2014.10 153.4 152.9 60.6 67.3 (-3.5) 8.96
2014.11 154.8 151.4 70.1 65.4 (-1.9) 9.33
2014.12 158.7 153.8 78.0 (63.5 projected, -1.9) 11.24
2015.01 141.9 137.3 67.0 (61.3 projected, -2.2) 9.46
2015.02 129.1 126.0 44.8 (59.6 projected, -1.7) 9.92
2015.03 125.9 124.6 38.4 (57.2 projected, -2.4) 16.14
2015.04 128.8 129.7 54.4 (54.6 projected, -2.6) 10.73
2015.05 120.0 122.6 58.8 (52.4 projected, -2.2) 8.29
2015.06 (121.1)   27.1 (2A)/ 90.4 (2B) / 71.1 (2C) (49.6 projected, -2.8) (7.8)

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.