Friday 31 May 2013

CaK Post Flare Prom Lift Off Animation - 31st May


Friday was the last day of our holiday here in South Wales, and all week have been blessed with some really nice clear skies, I have a whole load of images i've not been able to get up on here because of limited internet, but all in good time. I've also been experimenting with how I record and process my CaK images with a view to recording the K2 & K3 layers of the Chromosphere in CaK wavelengths - there was some discussion on Solar Chat about it thanks to Bob Yoesle, and on Cloudy Nights Harald Paleske also made some valuable contribution to a discussion that was running parallel on there. After experimenting this week I came to the conclusion that whilst it is difficult to record it is most certainly possible...

Fast forward to early friday morning; I got up at 6am with a view of trying to obtain some high res CaK images while the air was still cool and the atmosphere still steady. After setting up I checked the GONG website for a quick look as to what was happening, to my surprise there was a prom lifting off around ar11756, a quick check revealed a small C-class flare had happened just over the limb. I pondered whether or not to start off in Ha and go for an animation but decided to stick with CaK. I'm glad I did; I could quite plainly see the prom on the laptop screen. I ran off a couple of images but in just a few minutes I could see the rapid movement so thought would try a CaK animation. Well the good news is it worked; using the 100mm scope at 2000mm focal length with the DMK31 camera I made a 40 frame animation that spans 30 minutes in time.

I know CaK animations on the disk aren't really effective due to the variable seeing, but on this i'm not too bothered about this. If you look carefully you can see the flickering spicule like features which are the K2 K3 layer, but what I am pleased about is how effectively the prom lift off was recorded. Just to clarify, this is a one shot, with the disk and proms recorded in the same exposure.

Eastern Mosaic Ha 30th May

Eastern Mosaic Ha colour by Mark Townley
Eastern Mosaic Ha colour, a photo by Mark Townley on Flickr.

CaK full disk 30th May

CaK full disk colour by Mark Townley
CaK full disk colour, a photo by Mark Townley on Flickr.

Taken with the 100mm scope at f6 with DMK31 camera, this is a 6 pane mosaic.

ar11756 cak 100mm f20 30th May

ar11756 cak 100mm f20 by Mark Townley
ar11756 cak 100mm f20, a photo by Mark Townley on Flickr.

A small surge prom is visible in CaK wavelengths in this shot.

ar11755 CaK 100mm f20 30th May

ar11755 CaK 100mm f20 by Mark Townley
ar11755 CaK 100mm f20, a photo by Mark Townley on Flickr.

ar11757 Cak 100mm f20 30th May

ar11757 Cak 100mm f20 by Mark Townley
ar11757 Cak 100mm f20, a photo by Mark Townley on Flickr.

Ha Double Stack Full Disk 30th May

The Coronado DS40 has taken a bit of a comeback: I have replaced the objective lens that was astigmatic with one that appears to be fine. The external etalons have been aligned with respect to each other and all has been mounted back on the original coronado tube assembly. While the focuser still needs some work to improve things it is at least now a usable scope. This should work well in winter months when the low altitude sun and poor seeing are a major consideration. The double stack image is really nice! I just wish I had one in more aperture!

Single stack full disk Ha 30th May

Taken with the 70mm PST mod at f11, this is a 6 pane mosaic taken with the DMK31 camera.

ar11757 ha 100mm f32 30th may

ar11757 ha 100mm f32 by Mark Townley
ar11757 ha 100mm f32, a photo by Mark Townley on Flickr.

ar11755 ha 100mm f32 30th may

ar11755 ha 100mm f32 by Mark Townley
ar11755 ha 100mm f32, a photo by Mark Townley on Flickr.

ar11756 ha 100mm f32 30th may

ar11756 ha 100mm f32 by Mark Townley
ar11756 ha 100mm f32, a photo by Mark Townley on Flickr.

ar11760 ha 100mm f16 30th may

ar11760 ha 100mm f16 by Mark Townley
ar11760 ha 100mm f16, a photo by Mark Townley on Flickr.

ar11755 ha 100mm f16 30th may

ar11755 ha 100mm f16 by Mark Townley
ar11755 ha 100mm f16, a photo by Mark Townley on Flickr.

ar11756 ha 100mm f16 30th may

ar11756 ha 100mm f16 by Mark Townley
ar11756 ha 100mm f16, a photo by Mark Townley on Flickr.

polar filaprom ha 100mm f32 30th may

ar11756 wl 30th May

ar11756 wl 100mm f32 by Mark Townley
ar11756 wl 100mm f32, a photo by Mark Townley on Flickr.

Taken with the 100mm frac at 3200mm fl with the DMK31 camera ar11756 looks very picturesque as it approaches the solar limb.

ar11757 wl 30th May

ar11757 wl 100mm f32 by Mark Townley
ar11757 wl 100mm f32, a photo by Mark Townley on Flickr.

At just over 3000mm focal length with the 100mm frac there are the slightest hints of the polygonal shape of the granulation visible. Taken with a DMk31 camera.

Thursday 30 May 2013

Ha Full Disk 29th May

Ha full disk colour by Mark Townley
Ha full disk colour, a photo by Mark Townley on Flickr.

Despite there not really being many particularly active regions, the sun seemed to have a bit of everything on show; sunspots, plage, filaments, filaproms, prominences and even some minor flare actiivty. This shot was taken with the 70mm PST mod at f11 with the DMK31 camera.

Big Prom - 29th May

big prom by Mark Townley
big prom, a photo by Mark Townley on Flickr.

A large prominence was visible coming over the suns eastern limb, easily visible and very obvious in the eyepiece. This shot was taken with the 70mm scope using a 2.5x powermate and DMK31 camera.

Tuesday 28 May 2013

ar11757 ha 28th May

ar11757 ha by Mark Townley
ar11757 ha, a photo by Mark Townley on Flickr.

This large spot that makes up this active region is typical of many of the current solar cycle; single, large, solitary circular spots with very little activity surrounding them. Fortunately there was a large prominence on the limb to add to the image. Taken with the 100mm PST mod at 1600mm focal length with the DMK31 camera.

ar11755 ha 28th may

ar11755 ha by Mark Townley
ar11755 ha, a photo by Mark Townley on Flickr.

Activity is slowly decreasing with this active region, but it still proves to be a photogenic subject!

ar11756 Ha 28th May

ar11756 ha by Mark Townley
ar11756 ha, a photo by Mark Townley on Flickr.

Some clear skies this morning, but rapidly moving clouds from 2 different directions and poor seeing meant the image wasn't as good as I would like but it still shows nicely ar11756 getting closer to the western limb dragging behind it a bright area of plage. Taken with the 100mm PST mod at f16 with the DMK31.

Micro Flare Animation - 26th May



After the burst of X and M class flares over the past couple of weeks the sun has been relatively quiet lately in comparison.  However just as I was considering packing up I took a final look and noticed a small micro-flare going off near the suns western limb.  Barely B-class in magnitude this was still the largest explosion then happening in a 4 light year radius.  The seeing and transparency were variable due to the heat of the day and passing clouds, but this animation, shot over a 12 minute period with the 100mm PST mod at 1600mm focal length with a DMK31 camera shows just how dynamic our star is!

Ha Full disk 26th May

Ha Full disk colour copy by Mark Townley
Ha Full disk colour copy, a photo by Mark Townley on Flickr.

Lots happening on our star on the bank holiday weekend with plenty of clear skies. The tuning wasn't spot on for this image, but there is lots to see.

ar11756 Ha 26th May

ar11756 ha by Mark Townley
ar11756 ha, a photo by Mark Townley on Flickr.

Lots of detail visible!

ar11755 Ha 26th May

ar11755 ha by Mark Townley
ar11755 ha, a photo by Mark Townley on Flickr.

Ar11755 is absolutely crackling with activity! Taken with the 100mm PST mod @ 1600mm fl with the DMK31.

ar11757 Ha 26th may

ar11757 by Mark Townley
ar11757, a photo by Mark Townley on Flickr.

New active region AR11757 has recently rounded the limb. 100mm PST mod @ 1600mm fl with DMk31.

Sunday Prom - 26th May

prom by Mark Townley
prom, a photo by Mark Townley on Flickr.

A delicate prom was visible!

Filament - 26th May

big filament by Mark Townley
big filament, a photo by Mark Townley on Flickr.

There was a huge filament visible on sundays sun using the 100mm PST mod at 1600mm focal length with the DMK31 camera.

CaK Full Disk 26th May

There was lots to see on sundays sun in CaK wavelengths. Taken with the 100mm @ f5 with the DMK31 camera.

ar11757 CaK f20 26th May

ar11757 CaK f20 by Mark Townley
ar11757 CaK f20, a photo by Mark Townley on Flickr.

A slightly shorter focal length here - only 2000mm with the 100mm scope as the seeing was starting to deteriorate a bit. This shows the new active region (well doesn't look very active really!) AR11757. More interestingly on the limb there is a faint halo, similar to the spicule layer in Ha images, however this is the K2 and K3 chromosphere layers. This is something i want to explore further from an imaging perspective.

AR11755 CaK 26th may

AR11755 CaK by Mark Townley
AR11755 CaK, a photo by Mark Townley on Flickr.

More images from sunday mornings fantastic seeing in CaK wavelengths. 100mm @ 2500mm fl DMK31 camera.

Monday 27 May 2013

AR11756 Hi Res Cak 26th May

AR11756 Cak by Mark Townley
AR11756 Cak, a photo by Mark Townley on Flickr.

I'm away on holiday at the moment on the Pembrokeshire peninsula in West Wales, and for once are surrounded by miles in each direction by fields and trees, go further than that and are surrounded by the sea. This is quite clearly having a positive effect on the seeing conditions, certainly compared to ring of concrete, tarmac and roof tops that encircles me for miles and miles back home at Brierley Hills. I was set up and observing by 7am and as soon as I could see the image on the screen I knew the seeing was exceptionally good, and so using the Televue 2.5x powermate upped the focal length with my 100mm refractor to 2500mm; normally i'm struggling at half of this... By using the lunt solar wedge with no neutral density filters as an ERF I am able to keep exposure time short, however I think if I pushed the focal length any longer I really would have spoiled the image with longer exposure time causing smearing as a result of the seeing. This setup is allowing a 5% energy pass from the solar wedge at CaK wavelengths, but to keep exposure times as short as possible another route is going to be needed; one possibility is to use an UV hot mirror from Edmunds optics. This would provide an OD3 block of wavelengths longer than 400nn, but would allow transmission at 393nm in excess of 95%. At focal lengths in excess of 2000mm this extra light could be very useful at freezing the seeing. I have recently discovered if it possible to keep the exposure shorter than 1/1000th of a second, this really does allow a higher quality of frame to be recorded, I have found this to apply at both CaK and white light (540nm) wavelengths. Another experiment to pursue!

Wednesday 22 May 2013

Ha Full Disk 19th May

Ha full disk colour by Mark Townley
Ha full disk colour, a photo by Mark Townley on Flickr.

This 6 pane mosaic was taken with the 70mm PST mod at f7 with the DMK31 camera. There is lots to see on our star at the moment with numerous active regions visible.

Active Regions Closeup - 19th May

closeup bw by Mark Townley
closeup bw, a photo by Mark Townley on Flickr.

Taken with the 100mm PST mod at f16 this mosaic shows some lovely magnetic activity on our star!

Surge Prom - 19th May

small surge prom colour by Mark Townley
small surge prom colour, a photo by Mark Townley on Flickr.

This little spike, indicative of an active region about to round the solar limb is called a surge prominence. It was taken with the 70mm PST mod at f14 with the DMK31 camera.

ar11745 19th May

ar11745 colour by Mark Townley
ar11745 colour, a photo by Mark Townley on Flickr.

This active region was crackling away! Taken with the 70mm PST mod at f14 with the DMK31 camera.

The Sweltering South East 19th May

The south eastern quadrant of the sun was seething with activity this sunday. This mosaic was taken with the 70mm PST mod at f14 with the DMK31 camera.

Fiery Proms - 19th May

colour proms by Mark Townley
colour proms, a photo by Mark Townley on Flickr.

Some nice prominences visible this sunday!

Proms 19th May

proms bw by Mark Townley
proms bw, a photo by Mark Townley on Flickr.

C8 flare 19th May

c8 flare by Mark Townley
c8 flare, a photo by Mark Townley on Flickr.

Tuesday 14 May 2013

Mega-Prom Liftoff - 13th May

prom widefield by Mark Townley
prom widefield, a photo by Mark Townley on Flickr.

At the same time an X-class flare was erupting on the eastern side of the solar disk, on the western limb a huge prominence was lifting off. This shot was taken seconds before clouds finally came in and called a halt to observing for the day.

Post Flare Loops - The Movie... 13th May

I couldn't believe my eyes today to have seen a X2.8 class flare erupting away on then eastern limb of the sun, it had just happened and the post flare loops were plain to see in the eyepiece. Knowing these are very dynamic plasma loops I decided to set up the 70mm PST mod at f14 with the DMK31 and record a timelapse of it.  This represents just over 20 minutes in the life of our star and is an animation made up of 31 frames, each made up from simultaneous 1000 frame avis, from which the best 100 were stacked in Autostakkert2.

Ha Full Disk - 13th May

Ha full disk by Mark Townley
Ha full disk, a photo by Mark Townley on Flickr.

Imagine my surprise today when I looked at our star and saw not only an X class flare in progress on the eastern limb, but a huge prom lifting off on the western limb. This was taken with the DS40 @ f16 with the DMK31.

Saturday 11 May 2013

1927 UK Total Solar Eclipse


I have been fortunate enough to obtain an original cutting from the Times newspaper dated June 30th 1927 showing a lovely picture of the total solar eclipse taken by the  then  Astronomer Royal from Giggleswick in Yorkshire.  I decided to find out a bit more about the image that is presented scanned above and was fascinated by the background to it, so, given the cloudy skies we are currently graced with in the UK have decided to do a write up on this for the blog. The following is an overview of what I found.


June 1927 saw Britain in the grip of eclipse fever. A total eclipse of the sun, the first to be visible in Britain for more than 200 years, was predicted for 29 June. The path of totality ran across North Wales and Central England, from Criccieth in North Wales to Hartlepool on the east coast. The newspapers showed little interest in the event until the last moment, but other bodies were quick to respond.


'Your only chance until 1999' read the poster from rail company LNER, going on to advertise a pamphlet available from LNER inquiry offices which contained information about the event from the British Astronomical Association. London Midland and Scottish Railway suggested that vacations should be taken in west coast resorts from which the eclipse could be viewed. The list included Blackpool, Colwyn Bay and, more surprisingly, Liverpool.

The area around Giggleswick and Settle was considered to be one of the best sites for observing the eclipse. Eminent observers, including the Astronomer Royal Sir Frank Dyson, gathered at Giggleswick School with a collection of instruments from the Royal Observatory . These had been assembled at Greenwich and dispatched to Giggleswick by Admiralty lorry a few weeks before the event, according to the account in the Journal of the British Astronomical Association.

Around 2,000 people travelled by rail to the totality area from all parts of the country, some arriving only at the last moment. LNER's Flying Scotsman broke down en route and caused an hour's delay to 12 trains carrying spectators. Road traffic reached unprecedented levels. The Yorkshire Post reported that in just 40 minutes no fewer than 225 vehicles passed on the road between Boroughbridge and Wetherby.

People travelled in charabancs, by motorbike and on push bikes. Some even walked. Others took to the water. The Liverpool to Isle of Man ferry was crowded with passengers, many of whom stayed on deck to dance through the night. All this for an event which lasted 23 seconds.
The numbers watching the eclipse could certainly be counted in millions. Official figures for Giggleswick and Settle alone put the number who congregated in the area at between 70,000 and 100,000.
Sadly, the weather prevented more than half of those watching from seeing the event. The day proved to be cloudy, wet and windy. Later analysis showed the summer of 1927 was the worst for 50 years.

The following extract is from the Report of the Astronomer Royal, Sir Frank Dyson, to the Board of Visitors, 2 June 1928.The path over England of the 1927 solar eclipse

A'n expedition to observe the total eclipse of the Sun on June 29 was kindly accomodated on the school grounds at Giggleswick. The principle part of the programme was to photograph the Corona on a large scale with a 6-inch lens of 45-feet focus; to photograph the spectrum in the infrared with a Littrow spectrograph; and to compare the intensity of the Ca doublet in the infrared with the H and K lines by means of a small dispersion Littrow spectrograph. The weather previous to the eclipse was extremely bad, but the eclipse itself was observed through a break in the clouds. Small-scale photographs were also secured from an aeroplane kindly placed at the disposal of the Observatory by the Daily Mail. By permission of the Hydrographer of the Navy two observers from Greenwich were accommodated on board the Survey Ship H.M.S. Fitzroy which was engaged near the belt of totality in the North Sea. Owing to clouds no results were obtained. A full report is given in the Monthly Notices of the Royal Astronomical Society, Vol. 87, p. 657.'

The following link goes to an article from the Journal of the British Astronomical Association which provides a fascinating and in depth account of the eclipse.