Solar Activity 22 Mar

[brianb]

The morning dawned cloudy after overnight rain but a clearance developed during the morning. Sadly it was short lived, heavy showers soon moving in, but I did manage to observe between the front clearing and the arrival of the first shower.

The overview shots show a Sun which is steadily becoming less active.

2010 Mar 22, 1003 UT. Coronado PST CaK @ f/10, DMK41.

2010 Mar 22, 1008 UT. Solarscope 60 @ f/5, DMK41. (Disc and proms exposed seperately)

AR1056 has a medium sized "white light" spot and several spotlets but there is no other activity visible in white light.

2010 Mar 22, 1027 UT. WO FLT 110 @ f/28, Baader solar film (ND 5.0), DMK21.

AR 1056 is also interesting in CaK and in Ha, where it is enhanced by the persistent filament to its west:

2010 Mar 22, 1034 UT. WO FLT 110 @ f/21, Lunt B1200 CaK diagonal, DMK21

2010 Mar 22, 1011 UT. Solarscope 60 @ f/24, DMK21

The pair of filaments in the south east sector remain a prominent feature in Ha. Very interesting how the long filament maintains its tight shape in the apparent absence of magnetic activity nearby ... obviously there is a strong magnetic field at the altitude of the filament if not at chromospheric level!

2010 Mar 22, 1010 UT. Solarscope 60 @ f/24, DMK21.

Prominences are not remarkable. There is a smallish, low "hedgerow" on the west limb and another on the east limb.

1014 UT. SV60 @ f/24, DMK21

1015 UT. SV60 @ f/24, DMK21

The largest prominences are actually on the north east limb, though they're pretty faint:

1016 UT. SV60 @ f/24, DMK21

Transparency very good though with building shower cloud. Seeing fair but with moderate boiling when using the FLT 110. Temperature 11C (dropping to 7C as showers arrived), wind W force 3-4 gusting 5.

[davidscanlan]

Lovely pics :-)

This is one thing that has kept me coming back to the sun for decades now...the fact that it is never the same and there is always something new to see

[Macavity]

Perhaps a bit OT re. the imaging, but:

Is there a decent book, that goes a little beyond the mere naming of solar features, to explain their possible interrelationships? It must indeed be interesting to at least speculate what's going on in these splendid images...