Solar Terrestrial Activity Report

Activity chart

Last major update issued on June 11, 2015 at 06:30 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 unsettled on June 10 due to effects from CH671. Solar wind speed at SOHO ranged between 563 and 648 km/s.

Solar flux at 20h UTC on 2.8 GHz was 135.4 (decreasing 9.7 over the last solar rotation). The 90 day 10.7 flux at 1 AU was 125.7. 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: 32333223 (planetary), ******22 (Boulder).

The background x-ray flux is at the class B7 level.

At the time of counting spots (see image time), spots were observed in 12 active regions using 2K resolution (SN: 233) and 8 active regions using 1K resolution (SN: 133) SDO images on the visible solar disk.

Region 12360 [N14W44] decayed slowly and produced 2 level C flares.
Region 12361 [N19W15] decayed slowly and was mostly quiet.
Region 12362 [N07W10] decayed losing mature penumbra and spots.
Region 12364 [S05E09] decayed slowly and quietly.
Region 12365 [S13E08] gained spots and has polarity intermixing. Further C class flaring is possible.
Region 12366 [N18E07] gained penumbral area and was mostly quiet.

Spotted regions not numbered (or interpreted differently) by SWPC:
S4530 [N12W01] was quiet and stable.
S4531 [S09E21] was quiet and stable.
S4534 [S22W14] was quiet and stable.
S4535 [S07W12] was quiet and stable.
New region S4536 [S15W28] was observed with penumbra spots.
New region S4537 [S19E86] rotated partially into view and was the most active flare producer during the day. M class flaring is possible.

C2+ flares:

Magnitude Peak time (UTC) Location AR Recorded by Comment
C2.4 (LDE) 00:57   12365 SDO/EVE C1.8 @ GOES15
C2.5 01:41 N13W33 12360 GOES15  
C6.0 02:26 S19E90 S4537 GOES15  
C3.1 12:44   12360 SDO/EVE  
C3.3 13:05   S4537 GOES15 C4.0 @ SDO/EVE
C2.2 18:08   S4537 GOES15  
C2.9 20:22   12361 SDO/EVE  
C2.7 20:36     SDO/EVE uncertain, either 12361 or S4537
C2.1 21:28   12365 SDO/EVE C1.5 @ GOES15

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

Coronal mass ejections (CMEs)

June 8, 10: No obviously Earth directed CMEs were observed.
June 9:  A partial halo CME was observed in LASCO imagery late on June 9 and early on June 10. The source is uncertain but may be associated with a 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 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 mostly quiet on June 11-12. Effects from CH672 could cause quiet to active conditions on June 13-14 with a chance of minor storm intervals.

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       S03W66          

 

12360 2015.06.01
2015.06.03
20 35 19 N15W43 0070 EAI EAI images/AR_12360_20150610_2345.png images/AR_12360_20150609_2345.png  
12361 2015.06.03
2015.06.04
3 15 7 N17W16 0020 CSO CRO location: N19W15
12362 2015.06.03
2015.06.04
7 16 9 N06W13 0050 CSO DAO

location: N07W10

S4526 2015.06.04       S12W27            
12365 2015.06.05
2015.06.06
4 17 6 S13E07 0060 CAO CAO area: 0140

beta-gamma

reversed polarities

12364 2015.06.05
2015.06.06
2 5   S07E11 0010 AXX BXO

location: S05E09

12366 2015.06.06
2015.06.07
9 12 9 N17E05 0040 DAO DAI area: 0100
S4530 2015.06.07   1 1 N12W01 0004   AXX  
S4531 2015.06.08   4   S09E21 0009   BXO  
S4532 2015.06.09       N07E02          
S4533 2015.06.09       S32E37          
S4534 2015.06.09   2   S22W14 0004   AXX  
S4535 2015.06.09   2 1 S07W12 0005   AXX  
S4536 2015.06.10   3 1 S15W28 0007   AXX    
S4537 2015.06.10   1   S19E86 0020   AXX    
Total spot count: 45 113 53  
Sunspot number: 105 233 133  (total spot count + 10 * number of spotted regions)
Weighted SN: 70 136 76  (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): 63 82 73 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 (122.5)   30.5 (2A)/ 91.5 (2B) / 69.4 (2C) (49.6 projected, -2.8) (8.2)

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.