There are currently 6 sunspot groups visible on the solar disk. The most prominent groups, NOAA 2157 and 2158, are decaying. These groups still have spots of opposite magnetic polarity close to each other. A total of 7 C-class flares were recorded. The strongest flare of the period was a C3.3 peaking at 20:12UT. It occurred in an unnumbered sunspot region close to the southwest limb. NOAA 2166 is a small group embedded in a large plage area in the northeast quadrant, and produced only a C1 flare. Two filament eruptions were observed around 23:50UT and 03:40UT, but the associated CMEs were not Earth directed. Other CMEs, first observed by SOHO/LASCO on 12 September at 18:24UT and 21:48UT, were related to backside events and will not affect Earth. The proton event related to the X1 flare ended at 23:10UT. Further C-class flaring is expected, with a chance on an M-class flare. The arrival of the halo CME related to the X1 flare from 10 September was observed by SOHO/CELIAS as a shock in the solar wind on 12 September at 15:27UT. Wind speed increased abruptly from 430 to 670 km/s, and further increased to a maximum of nearly 800 km/s around 22:00UT. Bz was oriented southward between 20:30 and 22:00UT with maximum values near -17nT, then abruptly turned northward to steady values around +20 nT. The period between 21:00UT and 24:00UT was geomagnetically the most intense, with Kp reaching 7 (strong geomagnetic storm), and local K-indices at Dourbes and Potzdam reaching 6 (moderate storming). Geomagnetic conditions then quieted down, with currently unsettled to active conditions observed. Quiet to unsettled geomagnetic conditions are expected, with locally a brief active period possible in the aftermath of yesterday’s geomagnetic storm. SIDC
The X1.6 flare from 10 September was associated with an asymmetric full halo coronal mass ejection (CME). It was first seen by SOHO/LASCO at 18:00UT and had an average plane-of-the-sky speed of about 800 km/s. The CME is expected to arrive at Earth on 12 September around 21:00UT (+/-12 hours). It is not expected to interact with a previous halo CME from 9 September. Major to severe geomagnetic storming is expected, pending the orientation of the magnetic field of the plasma cloud. Starting around 21:00UT (10 September), a gradual increase in proton flux has been observed. It is currently above the event threshold near 30 pfu. This is only a minor radiation event with limited consequences for HF communication in the polar regions. SIDC
During last 24 hours four M-class flares were reported, and the strongest one was a M2.7 flare which originated from the Catania sunspot group 81 (NOAA AR 2087). The flare peaked at 10:21 UT on June 12 and was possibly associated with the CME (based on SDO/AIA data). More will be reported as soon as coronagraph data become available. The X1.0 flare (peaking at 09:06 UT) on June 11, M3.9 flare (peaking at 21:03 UT) on June 11 and the M2.0 flare (peaking at 04:21 UT) on June 12 were associated with narrow CMEs which will therefore not arrive at the Earth. The faint halo CME first seen in the SOHO LASCO C2 field of view at 14:36 UT, on June 10 had angular width of about 270 degrees. The bulk of the CME mass was directed northward from the Sun-Earth line. Currently available data give no indications about possible on disc signatures of the CME. We do not expect this CME to arrive at the Earth. The faint partial halo CME first seen in the SOHO LASCO C2 field of view at 18:00 UT, on June 10 had angular width of about 180 degrees and the bulk of the CME mass directed north-east from the Sun-Earth line. From the currently available data it seems that the CME was associated with the flare at E170 as seen from the Earth, and will therefore not arrive at the Earth. We expect C-class, M-class and X-class flares in the coming hours, in particular from the Catania sunspot groups 81, 69 and 76 (NOAA AR 2087, 2080 and 2085, respectively). Due to the position of the Catania sunspot groups 69 and 76 (NOAA AR 2080 and 2085, respectively) on the western solar hemisphere, we maintain the warning condition for a proton event. The Earth is still inside the fast solar wind (speed of about 500 km/s). The interplanetary magnetic field magnitude is about 4 nT. The geomagnetic conditions are at the moment quiet and expected to remain so in the following hours. The glancing blow associated with the halo CME from June 10 is expected to arrive at the Earth in the morning of June 13, and it might result in active geomagnetic conditions. SIDC
Two X-class flares were observed today, both originating from the active region which just rotated from the behind of the east solar limb. The impulsive X2.2 flare peaked at 11:44 UT and the second X1.5 flare peaked at 12:52 UT. The SDO/AIA data indicate that the flares were possibly associated with the CMEs. No coronagraph data are yet available. SIDC
NOAA 2035, already behind the west limb, produced an X1.3 flare peaking at 00:27 UT. No obvious proton flux increase has been observed so far. The event was accompanied by an EIT-wave towards the south (PROBA2/SWAP) and a CME (SOHO/LASCO and STEREO). The CME has a speed of about 500 km/s (CACTUS) and is directed away from Earth. There are currently 5 sunspot regions on disk. They are all quite small and have a quite simple magnetic configuration. An active region, responsible for backside CMEs on 22 and 25 April, is approaching the southeast limb. There’s still a chance on a C-class flare, in particular from the regions near the solar limb. There’s a decreasing chance on a strong flare from NOAA 2035 as it rotates further onto the Sun’s farside. Solar wind speed varied between 400 and 500km/s, and Bz between -5 and +4nT being mostly negative between 21:00 and 01:00UT. Hence, quiet geomagetic conditions were observed, with locally a brief active period. A small equatorial coronal hole passed the central meridian last night. The geomagnetic field may be impacted starting around 27 April. Geomagnetic conditions are expected to be quiet, with locally a brief active interval possible. SIDC
NOAA AR 2017 released an X1.0 flare with peak at 17:48 UT on March 29, associated with radio bursts, a full halo CME and an increase in GOES proton fluxes (not passing the threshold). This region is expected to produce M-class flares and probably X-class flares, it has a beta gamma delta magnetic configuration. A type II radio burst was detected at 11:52 UT, close in time of a C-class flare, this may mark the presence of another CME, but there is no data available yet.The full halo CME related to the X1.0 flare was first seen at 18:12 UT by LASCO-C2. The speeds measured are of 510 km/s (LASCO-C3), giving an expected arrival time (using DBM) to the Earth of 04:30 UT on April 2. Geomagnetic conditions are quiet, the situation may change when/if the CMEs from March 28 arrive to the Earth early on April 1 (expected 05:00 UT). SIDC
Video Credit: SDO, NASA; Digital Composition: Kevin Gill (Apoapsys)
Does the Sun change as it rotates? Yes, and the changes can vary from subtle to dramatic. In the above time-lapse sequences, our Sun – as imaged by NASA’s Solar Dynamics Observatory – is shown rotating though the entire month of January. In the large image on the left, the solar chromosphere is depicted in ultraviolet light, while the smaller and lighter image to its upper right simultaneously shows the more familiar solar photosphere in visible light. The rest of the inset six Sun images highlight X-ray emission by relatively rare iron atoms located at different heights of the corona, all false-colored to accentuate differences. The Sun takes just under a month to rotate completely – rotating fastest at the equator. A large and active sunspot region rotates into view soon after the video starts. Subtle effects include changes in surface texture and the shapes of active regions. Dramatic effects include numerous flashes in active regions, and fluttering and erupting prominences visible all around the Sun’s edge. This year our Sun is near its Solar maximum activity of its 11-year magnetic cycle. As the video ends, the same large and active sunspot region previously mentioned rotates back into view, this time looking differently.
The X4.9 flare of Feb 25 00:49 produced rising proton flux levels and a CME. The proton flux levels will cross the 10 pfu threshold for >10 MeV particles in the coming minutes. Meanwhile, incoming data revealed that the CME expanded to a full halo CME with a propagation speeds above 1500 km/s. Culgoora Observatory observed type II radio bursts with speeds of 2000 km/s and 700 km/s. As a consequence, we expect disturbed geomagnetic conditions but it remains hard to predict timing and magnitude as the CME has only a minor component in the direction of the Earth. SIDC
An asymmetric halo CME was observed by SOHO/LASCO-C2 with first measurement at 18:24 UTC. The main direction of propagation is to the southwest. The event was also observed in SOHO/LASCO-C3, STEREO A/COR2 and (partly in) STEREO B/COR2 imagery data. Based on time/height measurements of SOHO/LASCO data the initial CME speed is estimated at 2353 km/s. Analyses based on stereoscopy provide an estimate of around 1900 km/s. Using the drag-based propagation model (DBM) with a different speed values at 20 solar radii of 1800 to 2300 km/s, the arrival time of this CME is estimated on January 9 between 2:00 and 7:00 UTC.
In addition, also four C flares and one M flare occurred during the past 24 hours. Besides Catania sunspot region 98 (NOAA AR 1944), also Catania sunspot region 94 (NOAA AR 1947) was responsible for this flaring activity. On January 8 an M3.6 flare erupted from Catania sunspot region 94, peaking at 3:47 UTC. This event was associated with a narrow CME with first measurement in SOHO/LASCO-C2 at 4:36 UTC, which is not expected to be geo-effective. The event was combined with a metric type II radio burst with an estimated shock speed of 697 km/s (estimate from Learmonth).
The second proton event of this week is still in progress. Very high proton flux values were reached; with a maximum of about 950 sfu for >10MeV protons; near 50 sfu for >50MeV protons and near 4 sfu for >100MeV, during the past few hours.
The likelihood for more flares during the next 48 hours remains high; 99% for C flares, 75% for M flares and 50% for X flares. The proton flux is expected to further decline, but may rise again in case of more M or X flares. A shock in the solar wind data was observed on January 7 around 14:20 UTC. Solar wind speed, density and temperature show an abrupt increase, as well as the magnitude of the interplanetary magnetic field. The solar wind speed reached a value of 450 km/s, then was declining and currently has a value of 350 km/s. The magnitude of the interplanetary magnetic field has achieved a maximum value of 9 nT. The Bz-component is fluctuating between -8 and +4 nT. The shock is probably related to the arrival of the CME that erupted on January 4 at 21:25 UTC. The estimated NOAA Kp reached a maximum value of 3. Minor to severe storm (K=5 to 8) conditions are expected, due to arrival of the above mentioned CME of January 7. Aurorae might be seen at higher latitudes on January 9 until the morning of January 10 under clear sky conditions. SIDC
Equipment: Coronado 90 + SBIG 8300s + LX75 Processing: Photoshop Date: 01/08/14 Time UT: 15:00 Exposure 0.8 sec.
A X1.0 flare occurred on November 19, at 1026 UT (peak time), in NOAA AR 1893, close the west limb. The flare was associated with a metric type II burst, and an EUV coronal wave. There are preliminary observations of a CME linked to that event, as observed by the COR2 coronagraph on STEREO A, but only one frame shows the event and the speed is still unavailable. The position of the source region makes this event unlikely to be geoeffective, but more coronagraphic data are necessary to confirm this point.
INFO FROM SIDC
Equipment: Coronado 90 + SBIG 8300s + LX75
Time GMT: 17:00
Exposure 0.12 sec.