NLN Aurora Brief – November 1, 2015

Share Button

Aurora Brief Number 13 of 14
Other Briefs: Previous BriefNext Brief

Today on the Sun:

Active Region 2443 has continued to be active. It produced an impulsive M1 flare and over a dozen C-class flares. This was the first M class flare since October 17th. The region grew and maintained it’s magnetic complexity. Expect more flaring from this region over the next 24 hours.

Coronal Hole responsible for the expected G3 Aurora for November 2nd and 3rd
Coronal Hole responsible for the expected G3 Aurora for November 2nd and 3rd

The coronal hole pointed directly at Earth is producing a high speed wind stream that will impact Earth in a major way over the next couple days. SWPC has issued a G3-Strong geomagnetic watch for November 2nd and a a G2 (moderate) aurora watch for November 3rd. NLN has updated the 3-day forecast with the expected timings. These are based on the best data available but a +/- six hour window is possible. Either way, a strong storm is expected and it should reward aurora hunters. Above is an image of the coronal hole responsible for the potential storm, below, see the current timelines as currently predicted by SWPC.

NLN infographic of predicted Max KP Nov. 2 and 3
NLN infographic of predicted Max KP Nov. 2 and 3

Happy Hunting!

NLN Aurora Brief – October 31, 2015

Share Button

Aurora Brief Number 12 of 14
Other Briefs: Previous BriefNext Brief
Today on the Sun:

Activity has picked up today. Active region 2443 developed a delta spot and was responsible for a series of flares including a C7.9 flare and a two C5 flares. Throughout the day, these size of these flares steadily increased. The chart shows the each flare that happened in the day. The width of the bar shows the flare duration and the height of the bar shows the intensity.

Graph showing AR 2443 flares from 8/30/2015
Graph showing AR 2443 flares from 8/30/2015

Keep an eye on this region as it rotates into the Earth strike zone. If it continues the current pattern, it could produce an M-class flare in the next day or two.

Active Region 2443 in magnetogram from SDO
Active Region 2443 in magnetogram from SDO

Geomagnetic activity increased to KP-3 and produced some magnificent aurora storms in iceland late in the period. Here’s a tweet that Sigurdur William (@SiggiPhoto) posted from iceland:

Happy Hunting!

NLN Aurora Brief – October 30, 2015

Share Button

Aurora Brief Number 11 of 14
Other Briefs: Previous BriefNext Brief

Today on the Sun:

Flare activity increased slightly from yesterday with several C-class flares erupting mostly from active region 2443. AR 2443 was numbered in the period and now that it is in view after rotating fully onto the east limb. It was classified with a Beta magnetic structure but it is too early to tell if it is stable, growing or decaying. The other regions on the disk stayed remained stable and inactive.

A major CME event happened beyond the west limb. This was the second in as many days from roughly the same area. Both CMEs can be seen launching in LASCO C3 imagery. Notice the proton radiation “snow” on the second storm. As radiation from the explosion arrives at the camera, it appears as particles hitting the sensor. These show up as fast moving white specs. This event will not produce geomagnetic activity on Earth, so just enjoy the LASCO show.

First of Two CMEs shown in LASCO C3. October 28, 2015
First of Two CMEs shown in LASCO C3. October 28, 2015
Second of two CMEs shown in LASCO C3. October 29, 2015
Second of two CMEs shown in LASCO C3. October 29, 2015

As if that wasn’t enough, there were also two disappearing filaments in the last 24 hours. Both of these happened late enough that analysis on whether they produced CMEs won’t be complete until tomorrow. The CME launched by the filament mentioned in yesterday’s brief was determined to not have an Earth directed component. The CME from yesterday’s filament eruption is visible coming off the center right of the sun in the first animated GIF above, just after the large CME.

Finally, the big coronal hole continues to rotate towards the Earth strike zone. This feature represents the most likely source of aurora over the next week. It should start to influence the solar wind speed around 11/2 or 11/3. As mentioned before, this CH has a history of generating geomagnetic storming on Earth. Here is the twitter post NLN posted on the coronal hole’s previous rotation on Oct 6

This Day on 2003:

The X10 flare that was ongoing at the end of 10/29/2003 continued on through the beginning of 10/30. It produced another extremely fast (1900 KM/s) Earth-directed CME. The CME arrived at Earth just 19 hours after the flare. When it arrived the shock altered the Earth’s magnetopause so greatly that ACE satellites that collect readings were outside of the magnetopause for much of the storm. Bz reading most of the day stayed in the -15 to -30 range – which produced very strong geomagnetic activity. Active Region 486, which produced this flare, grew to 2500 millionths, by far the largest for this solar cycle. From this point forward the active region would begin to decay.

On Earth aurora hunters experienced a severe geomagnetic storm most of the day. KP ranged from 7-9 expect for a brief period between when the X17 flare impacts started to wane and the X10 flare CME shock arrived. Even in those relatively “calm” periods, KP remained at minor storm levels of KP 5-6.

Happy Hunting!