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Solar Highlights for January 16

Solar Rotation Nos: 2172 to 2173

Solar activity was at a similar level in January to last month. Once again the Winter weather reduced the number of observations received.
Here are the highlights for January 2016 together with a selection of images.


The New Year started off quietly with only one Active Region (AR2473) visible near the West limb of the Sun. It was a type Eso sunspot, on the southern hemisphere, and thought to be decaying, it suddenly generated an M-class solar flare in the early hours of the 2nd. While this was going on, AR2476 and AR2477 had appeared over the East Limb, and both were classed as type Cro and Hsx type sunspots on the 3rd. By the time AR2476 and AR2477 had reached the Central Meridian (CM) on the 7th they had not really changed much and this quiet state continued until they went over the W limb around the 12th.

AR2480 came over the E limb on the 7th, type Cao initially but slowly developed over the following few days becoming type Eso by the 11th. It was just north of the solar equator. By the 11th sunspots AR2483 had also developed and was clearly visible slightly farther north of AR2480. However, as AR2480 was nearing the W limb around the 15th, it suddenly became active with minor (C-class) solar flares.

As we approached mid-month, the Sun was generally quiet but AR2485 and AR2486 had appeared but both were quiet in nature. It was not until the 21st, when AR2487 (type Dao) and AR2488 (type Cro) had by then appeared either side of the solar equator, joining AR2486, that we saw a small upturn in sunspot activity as they crossed the Sun’s disk over the last few days of the month. AR2488 in particular showed some short bursts of development and was minor flare active around the 28th as it neared the W limb.

AR2489 was also easily visible by then. It reached the CM around by end of January and on the 30th was type Eko.

If you want to know more about the sunspot classification, see  on the SPA website.

SPA Sunspot Mean Daily Frequency (MDF): 2.69 
SPA Relative Sunspot Number: 36.78

A beautiful high double-arch prominence was drawn by Ian Lee and imaged by Richard Bailey on the W limb on the 6th.

A filaprom (filament and prominence joined together at the Sun’s limb) was also imaged by Mick Jenkins and drawn by Ian Lee on the 10th and 11th.

The 15th saw plenty of small prominences (and a pair of tree-like prominence on the SE limb) and much more activity on the disk in the way of filaments and plages.

A long smoke-stack prominence appeared on the NW limb on the 23rd and a large and complex tree-like prominences along the E limb. A lengthy chain-like filament was seen stretching away south eastwards, almost to the limb, following AR2487.

Activity in H-alpha really seemed to pick up in the last few days of the month. For example, on the 27th as AR 2488 and AR2489 were crossing the solar disk we had a tall prominence on the NE limb, along with a low hedgerow type along much of the E limb, plus some dusky filaments on the disk itself. On the 29th, a very lengthy cloud-like prominence along the SE limb (possibly left over from a recent CME on the 26th?) and a broad smoke-stack on the NW limb. On the 30th the cloud-like prominence on the SE limb was still seen with ease and was observed detached from the limb.

SPA Prominence Mean Daily Frequency (MDF): 5.01

Well done to Brian Gordon-States who observed the Sun on 22 days in January. Alan Heath and Jonathan Shanklin was not far behind on 20 days and 18 days respectively.

Detailed count records of Active Regions and Relative Sunspot Numbers came from: Richard Bailey, Michael Fullerton, Brian Gordon-States, Alan Heath, Mick Jenkins, Ian Lee, Jonathan Shanklin and Julia Wilkinson.

Images and drawings were supplied by: Richard Bailey, Carl Bowron, Mick Jenkins, Ian Lee, Cliff Meredith, Julia Wilkinson.

Geoff Elston


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