Solar Rotation Nos: 2234 to 2235
A turndown in sunspot activity with the Sun’s disc blank for nearly all of September. There were, however, some nice prominences in Hydrogen-alpha.
Here are the solar highlights for September 2020 together with a selection of images.
Sunspots
The Sun was spotless throughout September apart from the 22nd to the 24th.
Polar faculae were seen and imaged by Carl Bowron on the 14th at the north and south poles of the Sun.
AR2773 appeared near the east limb on the 22nd surrounded by faculae. It was a Solar Cycle 25 sunspot at latitude +28° and was type Bxo. It was hard to see. John Chapman-Smith observed faculae near the east limb while Carl Bowron imaged faculae and pores on the 22nd and Brian Gordon-States reported one Active Area in his sunspot count on the 24th. AR2773 seemed to disappear after that date.
SPA Sunspot Mean Daily Frequency: 0.00 (was 0.62)
SPA Relative Sunspot Number: 0.05 (was 7.86)
Solar Prominences, Plage, Filaments and Flares
There was a promising start to the month, notably the 1st when a hedgerow type prominence appeared on the west limb as well as a filaprom on the south limb, and a tall but dim detached prom on the east limb. However, we then had a quiet stretch until the 9th, the exception being a long flame-like prominence on the west limb on the 6th. Thereafter, when the prominences did appear, they were quite small. The 14th and 15th saw some small but bright proms on the north and south limbs and on the southeast limb on the 21st. There was another upturn in prominence activity around the 26th.
There were few filaments but they did appear on the 1st, 3rd, 6th, 13th, 14th, 20th; 26th and 29th.
Bright plage were seen on the 14th, 25th, 26th, 27th and 29th.
There were remnants of AR2773 still visible in H-alpha.
No solar flares were reported.
SPA Prominence Mean Daily Frequency: 1.12 (was 1.32)
Congratulations to Brian Gordon-States who observed 30 days in September. Alan Heath achieved 28 days and Jonathan Shanklin 26 days.
Detailed count records of Active Regions and Relative Sunspot Numbers came from: John Chapman-Smith, Brian Gordon-States, Michael Fullerton, Ian Lee, Lee Macdonald, Jonathan Shanklin and Bob Steele.
Images and drawings were supplied by: Carl Bowron, Ian Lee and Cliff Meredith.