Archive for September, 2008

The Sun 29-9-08 – Two Large Proms

September 29, 2008 Leave a comment

Woke up to unexpected clear blue skies with no cloud today which makes up for missing all the fun with that big prom yesterday. The same two proms were still visible in the SE and NW and seem to be very quiescent now with minor changes in structure over a number of hours. No surface activity visible.

Categories: Solar

The Sun 27-9-08 – Two fine proms

September 28, 2008 Leave a comment

Quiet on the surface today, but there are still two fine proms in the north and south. The prom to the south (upper left on disk shot below) developed markedly by the end of the day and grew in size. During the 28th this one enlarged even more, erupted and then reconnected to the surface with quite a few superb images and sketches of it appearing on the Cloudy Nights forum, sadly I missed the whole show as we were clouded out the whole day.

Categories: Solar

The Sun 26-9-08 – Nice proms plus last of AR11002

September 26, 2008 Leave a comment

After a foggy morning the murk lifted to reveal a cloudless sky this afternoon. The small active area that produced the eruptive event this morning could clearly be seen in the east. AR11002 is right on the west limb now and could hardly be seen in Ha, but was quite clear in CaK light. The proms in the north west formed a fine parade of hedgerows, small arches and flames. Normally I wouldn’t recommend using a 5X powermate on the PST as the results are usually pretty ugly, but I had another go today and the proms, while bloated, are not too bad considering the high magnification (see last two images below) – this is pretty much at the limit of what the PST can resolve.

Categories: Solar

The Sun 24-9-08 – AR11002 Fades

September 24, 2008 Leave a comment

Managed to get some images between 14.50 and 17.06 BST today after an alert on the CN solar forum that a big prom had been seen. Seeing was poor despite occasional patches of clear blue sky with much turbulence crossing in front of the sun which greatly reduced the resolution of fine features in the proms and AR. AR11002 is fading fast now and only tiny pores were visible today in CaK compared to the obvious spot seen yesterday. The large prom was a multiple arched affair.

Categories: Solar

The Sun 23-9-08 – A New sunspot AR11002

September 23, 2008 Leave a comment

Just arrived back from a short holiday in Cornwall to find that a new active region has rounded the east limb and is putting on a fine display. This one is a solar cycle 24 region too! Cleaning the DMK 41 with 100% cotton buds seems to have removed the persistent dust, but the DMK21 still has dust motes which will need more work to shift. Great to be able to see something other than background noise in the PST CaK today and it stood up well to high magnification of the spot group. Some fine arch proms on the north limb and smaller stuff in the south. The active region is still growing at the moment so this one should be interesting over the next few days.

Categories: Solar

The Sun 18-9-08 – Proms and quiet disk

September 23, 2008 Leave a comment

A glorious sunny day today for a change. Only two main proms in the north and no surface activity.

Categories: Solar

The Sun 13-9-08 – Various views of a quiet disk

September 13, 2008 Leave a comment

Amazing blue-sky blazing sun sort of a day for the most part although it did cloud up from the south by 4pm. Although visually clear the atmosphere had other ideas and was causing the familiar jelly dance on the suns surface, so prominence images in particular were not processing out as sharp as they could.

The CaK image also proved tricky to process as the surface is easy to burn out if the gain is set too high and again after stacking if too much wavelet processing is applied.
It was a quiet sun again today with the largest prom in the west and no real surface interest to view.

Categories: Solar

The Sun 12-9-08 – First Light for the PST CaK !

September 12, 2008 Leave a comment

Well the weather forecast was supremely optimistic again today with sun symbols all over the place at the Met Office. Up to 9am it was indeed clear and sunny, but the seeing was abysmal so I decided to wait and see if it improved. Of course it just went downhill from there with complete cloud cover till 4.30pm. A brief hole in the cloud between 4.30-5.30pm allowed me to setup the mount and try out the CaK for the first time. Getting the exposure just right is quite tricky in CaK light! I needed more gain than is usual for Ha, but when you get it right the detail just pops out on the screen. Lots of tiny bright plage spots and a much grainier surface than in Ha which resembles the white light views of the granular surface. Not much to see today of course but it will be great fun to image with when the activity levels rise. The quality of the image is superb, no astigmatism whatsoever. I took 1700 frames and had 243 to stack after aligning at a 90% quality threshold.

Also did a Ha disk. Fairly small proms around ths disk and no sign of the spots making up AR1001 which apparently appeared yesterday.

Categories: Solar

10-9-08 – A PST CaK joins my solar imaging setup

September 10, 2008 Leave a comment

Just bought this used PST CaK from Ben Ritchie. It is a replacement unit for his first PST CaK which was very astigmatic and had to be returned. This one has perfect focus judging by the images Ben has posted on the CN Solar forum and on his own website. I was hoping to be able to give a first light report on its imaging potential today, but the cloud never parted long enough to set everything up.

The CaK scopes allow imaging of a layer of the chromosphere which is cooler and lower than the view via a Ha filter. The Calcium K wavelength is at 393.4 nanometres and allows views of super granulation cells. Emerging flux regions can sometimes be seen forming in this layer before they become visible in Ha light and active region detail can persist in the Calcium view long after detail has been lost in Ha.

Categories: Equipment, Solar

The Sun 9-9-08 – Two Proms

September 9, 2008 Leave a comment

Got back home after work to find to find an unexpected blue patch in the sky – and some sun! And so the mad rush to get the EQ6 mount out and the laptop fired up plus camera connected ensued. I just had enough time to capture the two main proms before the sun dipped below the hedge at the back of the garden. Atmospheric conditions due to the low altitude sun were pretty awful and thin cloud kept passing too. Managed two 2000 frame runs though so I was more than happy. After processing the proms are not as sharp as I would have liked, but given the awful weather lately I am thankful for any brief views that are available.

Categories: Solar