SDAC Solar Image


Aurora Borealis

AR2192 the largest active region for 24 years

AR2192 a Flaring Giant of an Active Region

During the second half of October 2014 solar astronomers were treated to the spectacle of the largest sunspot (in area) for over 24 years and it was given the designated Active Region number of AR2192 or NOAA 12192. This active region may have been the same one as AR2172 that appeared during the last two weeks of September and then returned on the 17 October 2014. As the Sun rotates every 25.4 days at its equator when viewed from Earth [we orbit in the same direction as the Sun’s spin] we are able to monitor these active regions for about 13 days as they cross the face of the Sun before they disappear around the western limb and away from our view for about the same period of time if they survive for further rotation(s).

Comparison of AR2192 [marked 2014] with the largest sunspot of cycle 23 [marked 2001] and the largest sunspot ever recorded [marked 1947]

The 17th to 30th October proved to be a very exciting and tiring time for me as there were mainly long days of clear blue skies. I was able to remain in my observatory with the fan blowing cool air over myself and my laptop computer while my telescopes were outside tracking AR2192. These were immensely tiring days gathering and processing up to 100 gb of data a day while I was able to watch the live images on full screen view on my PC in anticipation of capturing some spectacular solar flares. I was working between 16 and 18 hours a day.

Here is a short film I made while I was filming an X2.0 flare on 27 October 2014

Here is a day by day resume of AR2192 flaring activities and some photos/animations of my captures of this major solar feature and the ones I missed I have permission from the US National Solar Observatory to use their GONG data to make and store the movies on my site:

On the 16 October 2014 AR2192 was just behind the eastern limb, it released an M4.3 [that I imaged] and 4 C-class solar flares. Link to daily flare report.

AR2192 releases an M4.3-class limb flare and I captured this sequence from 13:05 to 13:32 UT and this was  the first M-class flare from newly named AR.

AR2192 appeared on the Sun’s eastern limb on the 17 October and released 3 C-class flares before it was visible to us. Link to daily flare report.

On the 18th October it became visible and it immediately announced its presence with an M1.6 –class and seven C-class solar flares. Link to daily flare report

On October 19th it released its first X-class flare an X1.1 [peaked at 05:03UT] and seven C-class flares. Link to daily flare report

21 Oct 2014 GONG data

GONG data sequence for the X1.1 class solar flare

whight light movie

A short duration white light animation made on the 19 October 2014 from 09:34 to 09:45 UT Used DMK21 here all others DMK51 camera

It continued to grow and released five M-class flares [M3.9, M4.5, M1.4, M1.7 and M1.2] and nine C-class flares throughout the 20th October. Link to daily flare report

During the 21 October it released an M1.2 and nine C-class flares. Link to daily flare report


21 Oct white light

21 October 2014 white light mosaic image

21 October 2014 h-alpha

21 October H-alpha mosaic

21 October CaK mosaic at 10:02 UT

The 22 October saw the release of an X1.6-flare [it peaked at 14:28UT] that I was able to image and three M-class flares [M8.7, M2.7 and M1.4] and thee C-class flares. Link to daily flare report. Link to daily flare report

X1.6 Flare 22 Oct 2014

Here I caught the X1.6 flare but through thin clouds that make it flicker some what. Sequence from 14:30 to 15:48 UT and a close up below

Close up X1.6 flare

Close up of X1.6 flare event

October 23 saw the release of an M1.1 that I imaged and five C-class flares. Link to daily flare report

23 Oct 2014 M1.1

M1.1 event on 23 October 2014 from 09:46 to 10:11 UT

By October 24th it was at the midpoint of its rotational transit and released an X3.1 flare [peaked at 21:41UT so I made a GONG data movie of it - featured below] and an M4.0 that I imaged the only one to trigger a CME together with five C-class flares. Link to daily flare report

24 Oct M4.0 flare

Sequence of M4.0 flare the only one to release a CME this runs from 08:04 to 08:34UT

24 Oct H-alpha mosaic

24 October 2014 a H-alpha mosaic

CaK mosaic

CaK mosaic at 09:52 UT

CaK flare

24 October 2014 sequence in CaK from 09:59 to 10:19 UT showing small flares

white light still

24 October 2014 a still at 10:31 UT from a mosaic image run but finding some frames difficult to process - an ongoing project I think

X3.1 GONG data

24 October 2014 the largest flare an X3.1 it was after sunset at my location so sequence from GONG Big Bear data.

October 25 brought a further X1.0 flare that peaked at 17:08UT [after sunset for me] and seven C-class flares. Link to daily flare report

25 Oct movie

25 October 2014 from 13:31 to 16:16UT [just before sun down for me] a C5.1 followed by a C9.7 class solar flare

25 Oct 2015 flare

25 October 2014 here is the GONG data view of the X1.0 class solar flare

It released an X2.0 class flare that I imaged on the 26 October that peaked at 10:56UT, four M-class flares [M1.0, M4.2, M1.9 and M2.4] together with ten C-class flares. It also reached its maximum area on this day - see later. Link to daily flare report

Such active regions are measured in millionths of a solar hemisphere, where 1 micro-hemisphere, or MH, is about 600,000 square miles. This region topped out at 2,750 MH, making it the 33rd largest region out of approximately 32,000 active regions that have been tracked and measured since 1874. It is the largest sunspot seen since AR 6368, which measured 3,080 MH on Nov. 18, 1990.

26 October 2014 X2.0 flare

Here is the X2.0 flare on the 26 October 2014 from 11:31 [33 minutes after peak] to 12:28 UT variable seeing

The 27 October brought another X2.0-class flare that I imaged that peaked at 14:47UT, there were five M-class flares [M7.1, M1.0, M1.3, M6.7 that I imaged and M1.4] and six C-class flares. Link to daily flare report

M6.7 on 27 Oct 2014

Here is an animation of the M6.7 flare on the 27 October 2014 from 08:49 to 10:36 UT in reasonable seeing conditions.

27 Oct H-alpha mosaic

27 October 2014 a H-alpha mosaic at 13:40 UT

X2.0 27 Oct 2014

Here is a animation of the X2.0 flare on the 27 October 2014 sequence from 14:21 to 15:36 UT in variable seeing

Throughout the 28 October it released three M-class flares [M3.4, M6.6 and M1.6] and three C-class flares. Link to daily flare report

28 Oct 2014

Here is an animation from 12:19 to 13:15 UT showing flaring after a C5.2 event in sporadic cloudy cover.

By the 29th October it was on the western limb and released another five M-class flares [M1.0, M1.2, M1.4 that I imaged, M1.0 and an M2.3] together with seven C-class flares. Link to daily flare report

29 Oct

29 October mosaic image

M1.4 class flare

M1.4 class flare from 14:31 to 15:11 UT in generally poor seeing - this was my last attempt at the departing active region.

October 30th saw three M-class flares [M1.3, M3.2 and M1.2] and three C-class flares with three others attributed to a different active region number AR2201. Link to daily flare report


In summery this huge active region released six X-class flares, thirty three M-class and no less than eighty eight C-class flares during this transit between the 16 and 30 October 2014. What will it have installed for us in the second half of November?

To be continued ........

Andy Devey