Tuesday, 27 February 2018

Ex-AR12699 To Return Within a Week? 27th February

Taking a look at the SOHO data for the far side of the sun it would seem that AR12699 that passed over the suns limb over a week ago that there are still signs of activity visible.  Loops to the centre of the disk opposite indicate a bipolar active region, and whilst maybe not as active of it's previous rotation there is hope there may still may be sunspots visible.  At the very least a region of plage visible in CaK wavelengths, and possibly white light, should be visible, with the ex-active region likely proceeded with the view of prominences on the solar limb a day or so before the (ex?) active region itself is actually visible.  However the area develops, or not, it gives solar observers something to look forward to seeing in the coming days ahead.

Saturday, 24 February 2018

Supergranulation on a Blank Sun - 24th february

Todays sun is totally blank of all our usual features; active regions, sunspots and the like.  However look a little closer and this calcium image of our star shows 'Supergranulation', this pattern of convection cells on the Suns surface was discovered by A.B. Hart in the 1950's using doppler techniques to identify the flows of plasma on the photosphere.  Supergranulation has an approximate size of 30000km in diameter with a lifetime of about 24hrs and a surface flow speed of between 300m/s and 500m/s.  This image was taken with the ED60 at f6 with the homebrew CaK filter and the PGR Chameleon 3 camera, this first impressions with the scope at these short wavelengths is very favourable.  

I had planned on quite an observing session today, giving a number of scopes their first airing for the new year, however immediately on setting up the HEQ6 mount was dead and would not fire up; investigation revealed a fried inductor on PCB, likely caused by a short as can be seen in the image below.  Looks like a new board is in order. 

Saturday, 17 February 2018

A Blank Sun on Saturday - 17th February

After the excitement of the recent active region (ar12699) the sun has returned to a blank and quiet state more typical of our star as it descends into solar minimum.  There were some small proms and a few small hints of filaments, but, on the whole that was it for old yellow face. This shot was taken with a double stacked Lunt50 scope and a PGR Chameleon 3 camera.  Hopefully we'll get a bit more activity in the days ahead!

Sunday, 11 February 2018

Ha Full Disk - 11th February

The sun is getting ever higher with each passing day now, and each day gives an ever so slightly longer window for observation as old yellow rise clears the roof tops and trees of the urban skyline.  After dire conditions on Saturday I was optimistic Sunday may bring some clear skies as a low pressure system passed west to east into the north sea and pressure rose.  The air high above the UK was very cold and this led to much instability with towering cumulus shower clouds building which rattled through on a brisk north westerly wind.  The air in-between these clouds was very clear and the sky a rare deep blue so I risked a soaking and setup.  I'm still getting the hang of the Lunt Double stacked 50, as the ideal frame for imaging is just off centre.  I'm pleased with this shot though given conditions, it really was shooting between the clouds.  I'm more pleased to capture AR12699 which was just passing centre disk and may well be one of the last major active regions of the current solar cycle.

Friday, 9 February 2018

A Quick and Dirty Full Disk: 9th February

I got away from work early on Friday afternoon, and to my surprise the sun was visible in the slimmest of gaps, that is viewing with the scope through an open front door with passing cloud!  I decided to try the ED60 f6 with the Lunt wedge for a quick view.  The air was boiling away with the temperature differential in the open door, and was difficult to find focus - i'm not even convinced I did!  Still I was able to see AR12699 which is the largest active region for a while in this declining phase of the solar cycle.  Camera was the PGR Ch3 with a green filter and UV/IR cut.  Better than nothing, especially as that was what I was expecting for a while yet!

Thursday, 8 February 2018

A New Setup For The 2018 Solar Season

It's a new year and while we may be on a downward trend in this solar cycle there is still plenty to see on out star.  Here in the UK seeing conditions are often the main governing factor to successful imaging and as a result it is often the case that smaller apertures are able to deliver.  I was very happy to be able to use a Williams Optics 60mm f6 ED scope whilst at the eclipse in august 2017 and was very impressed with it's performance against the Borg50 scope.  A variation of the 60mm recently came up in the Astrograph sale and taking the opportunity to save a bit of money on the regular book price I bought one.  With a focal length very similar to the Lunt50 Ha scope it is easy to get a full disk with the PGR Chameleon 3 camera, and my 2" Lunt wedge fits in very nicely in it's 2" focuser.  I'm also very keen to see how this scope performs at CaK wavelengths too.  Cosmetically it is a nice match for the Lunt 50 on the side by side mount, and apart from imaging should be a great combination for outreach.  With the sun getting ever higher in the sky as we slowly head from winter towards spring, all I need is for us to be able to have some clear skies to get some observing in.

Sunday, 4 February 2018

Sunday Sunshine - 4th February

The weather has not been in any way lending towards observing the sun this winters season, endless cloud and grey is not the way toward seeing what is happening 150 million kilometres from Earth.  The weather forecast for this weekend was again unfavourable, but from dawn there were hints of brightness in the sky, and from about 11am solid skies turned into a mobile and transient cloud cover.  I had other commitments for the day but with an hours window I quickly got out the double stacked Lunt 50 and setup.  It was just nice to observe through the eyepiece, and, for several minutes this is what I did, scrolling in and out of the tuneable range of the Lunt taking in the doppler shift that was clear to see with the prominences.  I knew I was on band when the ghostly filament clouds snapped into view on the disk.  Despite the lack of activity it was nice to say hello with our solar friend at the start of a new year.  The little surge prom on the limb was interesting, and, if time allowed would have made for an excellent timelapse, particularly at higher resolution.  Taken with a double stacked Lunt 50 with kick a$$ moonlite focuser, a bit of barlow to get full frame and the solid and reliable PGR chameleon 3 camera.  Hoping for some clear skies next weekend now, fingers crossed!