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PostPosted: Sun Feb 15, 2015 10:29 am 
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The SOCIETY for POPULAR ASTRONOMY
Electronic News Bulletin No. 391b 2015 January 28th
SPA SOLAR ACTIVITY REPORT NOVEMBER 2014
By Geoff Elston Spa Solar Section Director
Solar Highlights for November 14
Solar Rotation Nos: 2156 to 2157
A slight recovery in sunspot activity from last month meaning we are still seeing at certain times a substantial amount of sunspot activity. There is plenty to see and the Sun still continues to surprise us. Here are the highlights for November 2014.
SPA Sunspot Mean Daily Frequency (MDF) for November: 4.74
SPA Relative Sunspot Number for November: 71.56
SUNSPOT SUMMARY
There was a quiet start to November. This was in contrast to October when we saw one of the largest sunspots in recent times, Active Region (AR)2198, cross the face of the Sun. We now know that while AR2198 was large and had a highly complex structure both visually and magnetically making it highly flare active, there was not a substantial rise in aurora activity here on Earth.
The first few days of November saw AR2203, which was then on the SE of the solar disk, develop-up quite rapidly. It even looked as if it might become flare active for a time as it neared the Central Meridian (CM) but it did not do so. A set of three images of AR2202, nearing the CM on the 1st, showed its development from 0941UT to 1325UT on the 1st.
On the 4th something was brewing on the eastern limb as there were reports of flare activity just over the limb. It was not until the 5th that AR2205 appeared over the limb and into view and as it did so it produced another flare (M-class). Although there were several Coronal Mass Ejections (CMEs) they did not have much effect on the Earth. An X-class flare was produced by AR2205 on the 7th at 1726UT and this too created a CME but this time there were a short-lived HF radio blackout. AR2205 continued to develop slowly as it approached the CM and it had produced several powerful flares as it did so. Once it was near the centre of the solar disk it seemed to quieten-down and once it was heading towards the W limb, it slowly decayed. AR2208 was clearly visible on the SE was the most interesting sunspot group to be seen.
The next day, on the 13th, former AR2192 returned over the E limb re-designated AR2209. It had decayed but was still quite large. On the 17th the following part of the whole group was designated AR2214. The whole sunspot group was glimpsed with the unaided eye on the 18th.
AR2214 took on an unusual appearance in looking like a bear’s paw print and it was dubbed the “bear’s claw” sunspot mainly, I believe, by US solar observers. There was not much flare activity this time around. AR2209 and AR2214 had reached the CM by the 20th.
Towards the end of the month AR2216 appeared over the E limb and on the 23rd both AR2209/14 and AR2216 were either side of the CM. AR2217 and AR2218 appeared over the limb by late November followed swiftly by AR2221 and AR2222 which were both flare active. At the end of November, the Sun was fairly active with sunspots particularly AR2222.
SUNSPOT MDF: 4.74
R: 71.56
PROMINENCES, PLAGE, FILAMENT AND FLARE ACTIVITY
There was a substantial prominence on the SE limb and smaller hedgerow type prominence on the W limb of the Sun on the 1st. It was not until about the 3rd that filament and plage activity started to pick up and by the 5th there was a lot of activity on the solar disk.
A beautiful loop prominence was seen near the E limb on the 4th. One Section member produced a 20-minute video of a solar flare erupting near AR2205 on the 5th at 0930UT and this was made available on the Solar Section News page of the SPA website at:
http://www.popastro.com/solar/news/newsdetail.php?... In addition, there was also a close-up of AR2205 in H-alpha showing tremendous detail in and around the sunspots.
A large prominence was imaged on the E limb on the 9th. I also received some very fine detailed short time-lapse videos of the same prominence but later that day. A tree-like prominence was seen on the SE limb on the 11th. I think this was separate from the prominences seen on the 9th. A whole disk image of AR2214 (the “Bear’s claw” sunspot) in blue calcium light on the 18th. There were also some great H-alpha images too.
AR2216 showed plenty of activity in H-alpha on the 22nd when it was only a few days over the SE limb. On the 30th there were both prominences around the solar limb and quite a few plages and filaments associated with the sunspots visible then (AR2222/AR2223 and AR2218, AR2219, AR2220 and AR2223.
PROMINENCE MDF: 5.13
SOLAR FLARES:
One solar flare was reported on: 4th 1130UT at the E limb.
Don’t forget the SPA Convention 2015 on March 28th at the Institute of Astronomy, Cambridge. This is where I like to show what the members of Solar Section do so well. I will be in touch soon to ask which of the many images you provide would you like to be shown at the Convention.
Bulletin compiled by Clive Down
(c) 2015 the Society for Popular Astronomy
The Society for Popular Astronomy has been helping beginners to amateur astronomy -- and more experienced observers -- for more than 60 years. If you are not a member then you may be missing something. Membership rates are extremely reasonable, starting at just £20 a year in the UK. You will receive our bright bi-monthly magazine Popular Astronomy, help and advice in pursuing your hobby, the chance to hear top astronomers at our regular meetings, and other benefits. The best news is that you can join online right now with a credit card or debit card at our lively website: www.popastro.com
________________________________________
Society for Popular Astronomy


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