Tag Archives: M-class flares

The Sun online and solar activity. 15.10.2014

солнце 15 октября

Two M flares occurred during the past 24 hours. The first, short duration,

M1.1 flare was released by a backside region close to the east limb at 10 S

(probably the return of M-flaring region NOAA AR 2173) and peaked at 18:37

UT on October 14. During the flare, very hot plasma (only visible in the

hottest SDO passbands) was ejected into space. The second M flare

corresponds to the post eruption arcade of the previous flare, started at

19:07 UT, reached its peak value of M2.2 at 21:21, and lasted until 00:19

UT on October 15. The GOES X ray flux curve has still not decreased to

background levels at the time of this forecast. The M1.1 flare is

associated with a halo CME first detected by LASCO C2 at 19:00 UT on

October 14. The CME had an angular width of about 270 degrees, with the

main bulk propagating towards the southeast at a speed of about 1700 km/s

according to the CACTUS software. The associated ICME is not expected to

become geo-effective since it is backsided. In the next 48 hours, M flares

are probable, especially from the region near the east limb that has

produced both M flares.Over the last 24 hours, solar wind speed observed by

ACE was highly variable between about 370 and 580 km/s, with current values

around 430 km/s. The magnitude of the Interplanetary Magnetic Field (IMF)

varied between 2 and 16 nT, with current values around 4 nT. This may be

the effect of the arrival of the CME from October 10. NOAA Kp indicated a

minor geomagnetic storm between 18h UT on October 14 and 3h UT on October

  1. K Dourbes was above 3 from 17h till 21h UT and went to minor storm

values between 20h and 21h UT. This is the result of the increased solar

wind speed combined with Bz values below -10 nT or thereabouts. Quiet

geomagnetic levels (K Dourbes < 4) are expected on October 15, 16 and 17.

 

The Sun Online and solar activity. october 04.10.2014

UPH20141001154003
INFO FROM SIDC - RWC BELGIUM 2014 Oct 03 12:20:19
Late on 2 October, a long duration M1.5 flare was quickly followed by a
powerful M7.3 flare, thus ending a 36 hours drought in flaring activity.
The two flares peaked resp. at 17:44UT and 19:01UT, and had their source in
the sunspot complex NOAA 2172/2173 which was rounding the west limb at that
time. The greater than 10 MeV proton flux stayed at nominal levels, and the
associated CME was directed to the southwest with no Earth-directed
component observed based on currently available imagery.
In the wake of the two medium flares, NOAA 2172/2173 produced a series of
C-class flares, the strongest being a C9.0 flare peaking at 06:48UT. The
x-ray background flux is still at the C1-level, but is expected to decrease
as the trailing portion of NOAA 2172 will have rounded the west limb later
today. The other 8 sunspot regions have a fairly simple magnetic
configuration, and have been quiet. 
C-class flaring is expected, with a small chance on an M-class flare from
behind the west limb from NOAA 2172/2173. Solar wind speed varied mostly between 350 and 400 km/s, and Bz fluctuated
between -5 and +4 nT. Geomagnetic conditions were quiet to unsettled, and
are expected to remain so.

The Sun Online and solar activity. September 14, 2014

There are currently 6 sunspot groups visible on the solar disk. Eight low-level C-class flares and one M-class flare were observed during the period. The latter reached a maximum of M1.5 at 02:16UT, and originated in NOAA 2157. The CME associated to this event was first observed by LASCO at 03:12UT. It had a speed of about 350 km/s (CACTus), but has no Earth-directed component. NOAA 2157 and NOAA 2158 continue their decay. However, together with NOAA 2164, they have spots of opposite magnetic polarity close to each other. Hence, they may still produce an M-class flare. Filament eruptions observed around 16:30UT (northeast quadrant) and 20:00UT (south of NOAA 2163) were not related to earth-directed CMEs.
M-class flares remain possible.  Solar wind speed decreased from about 600 km/s to 500 km/s, while Bz
decreased from +15 nT to a steady +6 nT. Geomagnetic conditions were quiet and are expected to remain so.
SIDC

Equipment: Coronado 90 +  Imaging Source DMK  + LX75
Processing: Photoshop, Avistack 300 frames
Date: 14/08/14
Time UT: 16:00
Exposure 1/500 sec.

Observatory Sponli

  

The Sun Online and solar activity. September 12, 2014

Over the last 24 hours, 2 M-class flares were produced by a currently unnumbered region at the northeast limb: an M2.1 flare peaking at 15:26UT, and an M1.4 flare peaking at 21:26UT. NOAA 2157 and 2158 produced 2 C-class flares each. The strongest was a C9.5 flare peaking at 02:24UT in NOAA
2157. Both of these regions have no longer a delta structure, but spots of opposite magnetic polarity are still close together. Based on the currently available imagery, no CMEs seem to have been associated to these flares. M-class flares are expected, with a chance on an X-class event.
On 11 September around 23:00UT, ACE observed a shock in the solar wind. Wind speed abruptly changed from about 350 to 480 km/s. Bz oscillated between -14 and +11nT. This was the arrival of the halo CME related to the M4-flare from 9 September. The impact resulted in active geomagnetic conditions (Dourbes), while Kp reached minor geomagnetic storm levels. Also the proton flux slightly increased.  The arrival of the halo CME from the X1 flare is expected for later today. Pending the orientation of the CME’s magnetic field, this may result in a major geomagnetic storm, with locally severe geomagnetic storming possible.
SIDC

Equipment: Coronado 90 +  Imaging Source DMK  + LX75
Processing: Photoshop, Avistack 300 frames
Date: 12/08/14
Time UT: 16:00
Exposure 1/500 sec.

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The Sun Online and solar activity. September 9, 2014

There are currently 8 sunspot groups visible. NOAA 2157 seems to be slightly declining and simplifying. NOAA 2158 developed some small spots to the west and south of the main spot. Except for the northern part, this main spot is now completely surrounded by opposite magnetic polarity flux. Both NOAA 2157 and 2158 retained their delta structures. Two C-class flares and 1 M-class flare were recorded. The strongest event was a long duration M4.5 flare peaking at 00:29UT and originating in NOAA 2158. SDO/AIA-imagery indicated post-flare coronal loops, coronal dimming and an EIT-wave. A type II radio-burst with an associated shock speed of 999 km/s was observed. The greater than 10 MeV proton flux, currently still enhanced at 2 pfu, has not increased in response to this flare (so far).   The M4.5 flare was associated to a halo CME first observed by SOHO/LASCO on 9 September at 00:06UT, with a plane-of-the-sky speed around 560 km/s . The bulk of the CME is directed away from the Earth (to the northeast), but there’s still a good chance Earth will be impacted by the CME-driven shock. Estimated impact time is 12 September at 03:00UT, with an uncertainty of 12 hours.    
There remains a reasonable chance on an M-class flare. The warning condition for a proton event remains in effect.
Solar wind speed was mostly between 350 and 450 km/s, with Bz oscillating between +5 and -5 nT. Geomagnetic conditions were quiet.
Quiet to unsettled geomagnetic conditions are expected for the next three days, possibly modulated by the high speed stream from a coronal hole that passed the central meridian on 5 September. On 10 September, there’s a chance on unsettled conditions with an isolated active period in response to the possible glancing blow from the 6 September CME. On 12 September, the impact of the halo CME related to the M4.5 flare from 9 September may result in active conditions and possibly a brief period of minor
geomagnetic storming. 
SIDC

Equipment: Coronado 90 +  Imaging Source DMK  + LX75
Processing: Photoshop, Avistack 300 frames
Date: 09/08/14
Time UT: 16:00
Exposure 1/500 sec.

Observatory Sponli

  

The Sun Online and solar activity. September 6, 2014

NOAA AR 2157 (Catania number 45) produced numerous C-class flares during the past 24 hours, the strongest of them being the C8.0 flare peaking today at 08:14 UT. This active region has  beta-gamma-delta configuration of its photospheric magnetic field, so we expect more flaring activity up to the M-level, mostly from this sunspot group. An isolated X-class flare is  possible but unlikely. The C8.0 flare was accompanied by coronal dimmings indicating the eruption of a CME. However, there is no SOHO/LASCO data yet to confirm the CME occurrence. A partial halo CME was detected yesterday first appearing in the LASCO C2 field of view at 19:24 UT. STEREO B EUVI data show that its source region was located on the far side of the Sun (filament eruption around N15E160 as seen from the Earth), so this CME will not have geomagnetic consequences. The solar proton flux is just below the SEP event threshold, so we maintain the warning condition for a proton event. Since around 04:00 UT today, the interplanetary magnetic field (IMF) magnitude is elevated (up to 12 nT) indicating the arrival of an ICME, probably corresponding to the partial halo CME detected on the Sun on September 2. Due to low solar wind speed (around 350 km/s), the geomagnetic conditions remained quiet to unsettled. The IMF now turned northward, so the geomagnetic conditions are quiet and are expected to remain so.
SIDC

Equipment: Coronado 90 +  Imaging Source DMK  + LX75
Processing: Photoshop, Avistack 300 frames
Date: 09/05/14
Time UT: 16:00
Exposure 1/500 sec.

Observatory Sponli

  

The Sun Online and solar activity. September 4, 2014

Since yesterday’s bulletin, solar activity was on the C-level, with the strongest flare being the C5.2 flare peaking yesterday at 21:24 UT in the Catania sunspot group 44 (NOAA AR 1255) close to the east-south-east limb. The same active region yesterday produced the M2.5 flare that was accompanied only by a weak and narrow CME. The solar background X-ray flux is currently around the C1 level. We expect flaring activity up the M-level, in particular from the Catania sunspot group 44.  The former
NOAA AR 2139 (that was responsible for the major eruption on the far side of the Sun on September 1) is now appearing from behind the east limb. The solar proton flux, although increased, has stabilized below the SEP event threshold. We maintain the warning condition for a proton event. The Earth is currently inside a slow (around 390 km/s) solar wind flow with average (around 5 nT) interplanetary magnetic field magnitude. The geomagnetic conditions are quiet and are expected to remain so.
SIDC

Equipment: Coronado 90 +  Imaging Source DMK  + LX75
Processing: Photoshop, Avistack 300 frames
Date: 09/04/14
Time UT: 16:00
Exposure 1/500 sec.

Observatory Sponli

  

The Sun Online and solar activity. August 26, 2014

Flaring activity continued at the same level with four C- and two M-class flares, originating from NOAA AR 2146. Two CMEs were observed in coronographic imagery, with NOAA AR 2146 as source region.
An asymmetric halo CME was visible in SOHO/LASCO C2 and C3 and STEREO B/COR2 data, with first measurements on August 25 at 15:24 UT (C2), 16:18 UT (C3) and 16:24 UT (STEREO B)  respectively. The CME was associated with a M2 flare peaking at 15:11 UT, dimming and type II and IV
radio bursts (shock speed estimated at 707 km/s by the Sagamore Hill station). The CME has a projected line-of-sight speed of 568 km/s (CACTus estimate). A second partial halo CME was visible in SOHO/LASCO C2 and C3, with first measurements on August 25 at 20:36 UT (C2) and 21:18 UT (C3). Also this CME was associated with an M-class flare (M3.9, peak at 20:21 UT). The CME is travelling with a projected line-of-sight speed of 761 km/s (CACTus estimate).
Both CMEs are mainly propagating in the western direction from the Sun-Earth line and might be interacting with each other. A shock might arrive in the second half of the UT day of August 28.  
More C- and M-class flares are expected, especially from NOAA ARs 2146 and 2149. An X-class flare is possible, but unlikely. Proton flux levels at > 10MeV have increased from 18:00 UT on, but remained
below the event threshold and are currently decreasing. A warning condition for a proton event, in case of more flaring, is issued. Solar wind speed slightly increased from 250 till 290 km/s. The amplitude of the
interplanetary magnetic field increased to 7 nT, with a varying Bz component. Geomagnetic conditions were quiet to unsettled and are expected to remain so until the combined arrival of the August 22 CME’s. This may potentially result in active geomagnetic conditions from the afternoon of August 26 onwards.
SIDC

 

The Sun Online and solar activity. August 22, 2014

Flaring activity is mostly originating from the North-East quadrant of the solar disc up to an M3.4 flare from NOAA AR 12149 near the NE limb on Aug 21 13:31. Continued M-flare activity is expected from this region, while also NOAA AR 2148 is expected to produce C-flares.Quiet geomagnetic conditions are expected in the coming  3 days: there are no high speed wind streams expected from coronal holes,  nor are there any new CMEs on the way to the Earth.
SIDC

Equipment: Coronado 90 +  Imaging Source DMK  + LX75
Processing: Photoshop, Avistack 300 frames
Date: 08/22/14
Time UT: 16:00
Exposure 1/500 sec.

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The Sun Online and solar activity. August 2, 2014

There are currently 9 sunspot regions on the solar disk. NOAA 2130 produced an M2 flare peaking at 14:48UT, and NOAA 2127 was the source of an M1.5 flare peaking at 18:13UT. The CME associated to this flaring activity was first observed by SOHO/LASCO at 18:36UT. This CME had a true speed of about 800 km/s, but the bulk was directed to the SE. Nonetheless, difference imagery detected the outline of a faint halo to the WSW, and was a near full halo as seen from the STEREO-A vantage point. Hence, a glancing blow of this CME can not be excluded and could impact Earth in the afternoon of 4 August.  NOAA 2127, 2130 and 2132 still have areas with some mixed magnetic polarity.  The CME associated to the 1 August (10:15UT) filament eruption, which took place in the same location as the 30 July filament eruption, was directed mainly to the north. It does not seem to have an Earth-directed component despite its proximity to the disk’s center.  Two 25-degrees long filaments in the NE and SW quadrant remained stable. C-class flaring is expected, with a chance for an M-class flare.
Solar wind speed increased from about 350 km/s to values between 400-450 km/s. Bz oscillated between -10 and +10 nT. Local geomagnetic conditions were quiet to unsettled, with Kp briefly reaching active levels just before midnight. No obvious signature from the CME associated to the 30 July filament eruption has been observed so far in the solar wind parameters. 
Geomagnetic conditions are expected to be quiet to unsettled, with locally a chance on active conditions as the solar wind may still be modulated by the 30 July CME (2 August) and the influence of a coronal hole stream (4 August).
SIDC

Equipment: Coronado 90 +  Imaging Source DMK  + LX75
Processing: Photoshop, Avistack 300 frames
Date: 08/02/14
Time UT: 16:00
Exposure 1/500 sec.

Observatory Sponli