NLN Aurora Brief – October 26, 2015

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Aurora Brief Number 7 of 14
Previous Brief: NLN Aurora Briefs – October 25, 2015
Next Brief: NLN Aurora Briefs – October 27, 2015

Today on the Sun:

Solar activity continues at very low levels with decreasing activity. Today the highest level of flare activity measured was a B9.7 flare from AR 2436. AR 2436 is still the most complex and largest region on the disk, it is slightly smaller than yesterday, but is still showing slight growth in its middle spots. It is unlikely to produce significant flaring unless it becomes more complex. The was a CME reported in LASCO imagery, but it appears to have come from a backsided event so it will not have any impact on Earth.

On Earth, The expected CME arrived right on schedule, but the orientation was not conducive to generating Aurora. The N/S component of the magnetic fields, the Bz, remained North nearly the entire period. For a CME impact to generate aurora generally it has to be oriented South. As of now, there is no way of knowing the orientation of a CME until it arrives at Earth – that is the primary reason so many geomagnetic watches leave disappointed aurora hunters as they expire.

This day in 2003:

Activity on the Sun in 2003 continues to heat up. Both regions 484 and 486 produced long-duration X1.2 flares. These flares both produced fast moving partial-halo CMEs. Both will arrive at Earth over the next couple days to start an impressive period of storming. In addition to the flares, two filaments, 18-degrees and 12-degree erupted and produced CMEs. Both of the filament related CMEs were well to the west (behind) of Earth and won’t impact the magnetosphere.

Magnetogram from the sun Oct 26, 2003 showing AR484 and 486
Magnetogram from the sun Oct 26, 2003 showing AR484 and 486

On Earth, activity was quiet, but a new watch is posted indicating possible minor to isolated major aurora storming on days 2 and 3

Happy Hunting

NLN Aurora Brief – October 25, 2015

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Aurora Brief Number 6 of 14
Previous Brief: NLN Aurora Briefs – October 24, 2015
Next Brief: NLN Aurora Briefs – October 26, 2015
Today on the Sun:

Once again, on the surface of the Sun activity is low and decreasing. Active region 2434 was the most active region but only produced three C1 flares and displayed evidence of decay as it rotated around the western limb. AR 2436 continued to decreased in size, but showed growth in it’s trailer spots and it’s total spot count increased slightly.

A G1 geomagnetic watch continues to be in effect for today. The expected CME arrived late in the October 24th period as expected. While it appears the majority of the CME passed Earth to the West (behind) and South of Earth, the shock was evident on EPAM and in solar wind data. When it arrived it was strong enough to produce aurora, however the orientation of the cloud so far has been North-pointed so far. The expected increase in KP will not materialize unless the Bz shifts to the south. Keep an eye on it, but this storm is likely not going produce a major storm. In these images, see the EPAM at the time the CME shock arrives and the solar wind data as visualized by www.spaceweatherlive.com

EPAM shows arrival of CME shock
EPAM shows arrival of CME shock
Solar wind data at the time of arrival of CME
Solar wind data at the time of arrival of CME

This day in 2003:

Active regions 484 and 486 continue to be the most magnetically complex regions, but the activity they produced decreased to moderate with 4 M-class flares. Similar to today’s activity, there were CME passages, but the Bz component of the magnetic field remained north – so there were few reports of aurora. A 10-degree filament lifted off the surface of the Sun, it produced a non-earth directed CME. The probability of x-class flares was set to 40% and M-class flares to 85%. The next days’s activity would prove the flare predictions accurate.

Happy hunting!

NLN Aurora Brief – October 24, 2015

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Aurora Brief Number 5 of 14
Previous Brief: NLN Aurora Briefs – October 23, 2015
Next Brief: NLN Aurora Briefs – October 25, 2015

Today on the Sun:

Very quiet on the surface of the Sun today, just a small set of B-class flares. It appears the long duration flare on Wednesday rearranged the magnetic fields and reduced the potential for flares. All active regions have decayed, losing spots, size and magnetic complexity. AR2436 remains the largest and most complex region, but is now classified as Beta. The chances for big flares are low again today.

Don’t let the quiet sun fool you! SWPC has posted a G1 geomagnetic storm watch for today and tomorrow with G1 Aurora predicted for late on the 24th. The CME from the long duration flare should arrive this evening providing European and North American aurora hunters a good chance for northern lights. EPAM is showing a consistent rise in protons indicating the CME is getting closer:

EPAM shows rise in protons
EPAM shows protons measured at ACE are rising in advance of the CME arrival

When the CME arrives, expect the KP to increase as the Earth’s magnetic fields respond. As KP goes up, the aurora will be visible at lower latitudes. You can monitor the KP live on our currnet live KP charts page. In the US, clear skies are expected on the eastern-most tip of Maine and through the middle of the country. In this map, the best viewing will be in the deep blue areas.

Cloudcover map for the time of the CME arrival
Cloudcover map for the time of the CME arrival

This day in 2003:

Active regions 484 and 486 continue to be large complex beta-gamma-delta regions producing strong flares. 484 produced and M1 flare, and 486 produced an M7 flare. The previous day’s X-class flares produced a large fast CME, but is was directed to the East (ahead) of Earth and did not produce aurora. The CME shock from the flares two days earlier arrived and produced a period severe storming. Many people saw the aurora, this would foreshadow much stronger stormed for just a week later

Happy Hunting!