Cone Nebula (SH2-273)

Hi All,

Still not able to get PHD to work. So here is an unguided image of the Cone Nebula. This is 50 x 2 minute subs in Ha. The Scope is the Takahashi Epsilon ED180 @ f2.8 and the Atik 4021. This gives a Field Of View (FOV) of 102’x102′.

I’m getting the data for RGB so will post a HaRGB image later.

For those who don’t know, if you hover the mouse over the image and click, you get a magnified image.

Geoff

Equatorial Platforms USA compact wooden platform for 52 degrees North – Photos of Platform & User Guide (Instruction Manual)

My latest acquisition, being testing with my Dark Star 12 inch Dobsonian telescope.

Equatorial Platforms USA 52 degree compact platform user guide scanned 19/3/2020

From my tests today, the power connection port is CENTRE POSITIVE (12V DC) – i.e. same as the cable used for powering HEQ5/EQ6 mount or my QHY10 camera. It certainly powers up using one of the 12V power supplies for my WD MyBook USB external hard disc drives – which is what I was using in photo below.

Andy

Observing and another wide image.

Sunday night was one of those rare occasions when a clear night is accurately forecast in advance. Shame it was work the next day, but the forecast meant I able to set up both imaging rigs and the dob in the daylight and get going as soon as the sun set..

The observing was pretty good- I really wanted to make the most of the winter targets that are now drifting away and had good views of Venus, M42, the Running Man and the Flame. Conditions were good so I had a go at the Horsehead with a number of eyepieces and filters, but no joy. Having seen it once (at a darker site) it always seems to be teasingly on the edge of vision- the bank that it sits in is often just discernible and so logically you would expect a gap in that bank to be visible too…

To make life easier I spent a bit of time on the Pleiades. It may sound funny, but after 5 years of looking at it, including 2 with the telescope I’m using now, it seems I’m only just now learning how to look at this. When I first look, the magnification of the scope (it’s 1650mm fl) makes the stars relatively sparse. Some strong nebulosity does appear quite quickly, but it’s only after literally minutes of just gazing around the object, wobbling the scope and moving just off the object and back on again that the filmy nebula away from the brighter bits emerges. Really gorgeous. And maybe I’m a just a bit slow on the uptake.

I then moved onto Perseus (which is in the darkest bit of sky for me)- looking at Mirium (lovely yellow/white double), Theta Perseus, Melotte 20 (better in the finder), M34 (not my favourite), the Double Cluster (always lovely), and Iota Cass (I couldn’t see the colours very well this time, which was a bit disappointing).

I then moved up to Ursa Major for M51 (it was quite high, the 2 cores were bright, and the bridge was visible, the arms less so, but a nice view all the same) and NGC 2403 which I recently imaged, but which was hardly visible in these skies. Next up was M106, but the clouds beat me to it and it was time to pack up.

Whilst enjoying the relatively balmy night (it didn’t hit the dew point until the very end) I also had the imaging rig on M106 (which I’ve yet to process) and the camera doing an 18mm field along the Milky Way. I’ve done two of these before; running the galaxy from bottom right to top left, and I had vague notions of turning It into some sort of super mosaic of the galaxy across the year, but it’s so much lower in the sky this time of year that it was impossible to frame it like that. I was also shooting into the light pollution over Burton, which gave me some wicked gradients across that wide view- here’s the stacked image after a stretch on it.

When I look at images like this it seems a miracle we can see anything at all through that murk. Pixinsight’s DBE tool did battle with it- and I’m going to call it a score draw- the bottom left corner was pretty much a lost cause, but after I cropped it out the rest of the image came out OK, with just a bit of vestigial lp gunk remaining. It seems really marked how much more sparse the galaxy is looking away from the core like this:

And here’s an annotated version:

 

Grand opening of Peter Bolas Observatory

Chris Lee, chief scientist at the UK Space Agency opened the observatory today, in the company of over 100 dignitaries, representatives of benefactors,  members of the group and their families, on one of the few rain-free days of the year so far!

It was a wonderful experience showing us what we can achieve together and giving us a platform for our future activities.

Andy

                             

     

A Great Big Thump

Came back from a nice family night out on Friday to a lovely clear view of 95%ish moon- had a lovely hour taking some pictures. After doing lots of DSO lately, where the pursuit of greater quality is leading to ever longer integration times it was nice to just wander round the disc of the moon and take (relatively) quick captures.

These are my 3 favourites- the same technique was used on all three- a one minute video using ASI224 camera, then Autostakkert to identify and stack the best 5% of frames and finally Pixinsight to crop and sharpen using the Multiscale tool (similar to Wavelets in Registax) and then tweak the levels.

First one is the Copernicus crater and associated impact debris. I tweaked the curves quite a lot to bring out the spoil from the impact. From Wikipedia, the crater itself is 93km wide, using the Pixel scale I make the main disk of debris around it 400km wide, whilst Wikipedia thinks the rays extend for twice that. That’s quite an impact!!!

Next up is another impact- here’s the smaller Proclus crater, with the rays of the impact spreading out over Mare Crisium:

Finally- here’s the Aristarchus Crater with Schroter’s Valley (which is the sinuous rille extending up from Aristarchus in the middle of the image) being really nicely illuminated on its southern wall.

 

Observing Log 6/3/2020 @ 22:00-7/3/2020 @ 00:30 – The Moon

Observing Log 6/3/2020 @ 22:00-7/3/2020 @ 00:30

Andrew Thornett, Alan and Angella Rodgers

Lichfield

  • Orion UK 10” Dobsonian Telescope
  • Explore Scientific 14mm & 9mm 100-degree AFOV eyepieces
  • Tele Vue Ethos 6mm eyepiece
  • Tele Vue Big Barlow x2

As a night with predicted cloud cover around 50%, this was a poor choice for astrophotography. A bright 10-day old moon meant that most of the deep sky was washed out, plus cloud quickly passed through obscuring faint objects as we tried to find them. It therefore seemed a poor choice for an evening of astronomy. However, Angella and Alan came around and the three of us spent a wonderful time observing the moon. Usually, we “experienced” amateur astronomers reject the moon but it such a wonderful object with so much detail. Tonight, we took the time to eke out more detail than I have seen before on the moon….not because I couldn’t but rather because I didn’t and after tonight’s experience I feel that this was an error on my behalf – I intend to spend far more time in the future getting to know our close celestial neighbour! I can see now why Patrick Moore used to spend so much time looking at it from his dark skies in Selsey with his 15” telescope when he could have looked at other things.

I also discovered tonight that I still adore my first love of visual observational astronomy – over the years I have done radio astronomy, astrophotography, spectroscopy, amateur telescope making, and all those are great in their individual ways, but getting out there with the telescope and eyepiece under the stars cannot be matched! Wow! Wow! Wow! I also love the Dobsonian telescope – so simple to use and set up, and such great stable views – although does need quite a lot of star-hopping skills but then I enjoy doing that too. No circuit boards to die, limited dependency on batteries (illuminated finders mainly and your torch!)

We also used good old-fashioned printed moon atlases tonight. In particular, we used two books tonight: (I) Thierry Legault and Serge Brunier’s New Atlas of the Moon 2006 which gives large labelled photographs of the moon day by day throughout its cycle and close-ups of particular regions, and (II) Antonin Ruke’s Atlas of the Moon 1990 – this latter very famous tome (mine is the much cheaper first edition) has vast numbers of labelled drawings of different areas of the moon.

We started our journey by identifying Phocylides and Wargentin craters – that make up a Ginger biscuit man shape (2 circles of slightly different sizes close together and easily picked out against other craters). We tried to identify both small craters between these two – but one was over side of moon so could not be seen.

From there we hopped to the ray crate Tycho, and followed the two parallel rays down to crater Bullialdus with its central peak which we could easily see. We then hopped to Gassendi and spent a lot of time on this crater. We could identify a breach in its side wall but had difficulties seeing all the features in its base that were visible on the photographs in the New Atlas of the Moon, even with the 6mm Ethos eyepiece. However, when I added in my 2x Big Barlow to give magnification 400x (1200mm focal length on scope) then they became visible and the view was amazing!

Wikipedia gives a description of the crater which accurately describes the view we saw, “Gassendi is a large lunar impact crater feature located at the northern edge of Mare Humorum. It was named after French astronomer Pierre Gassendi. The formation has been inundated by lava during the formation of the mare, so only the rim and the multiple central peaks remain above the surface. The outer rim is worn and eroded, although it retains a generally circular form. A smaller crater – Gassendi A – intrudes into the northern rim, and joins a rough uplift at the northwest part of the floor. The crater pair bear a curious resemblance to a diamond ring. In the southern part of the crater floor is a semi-circular ridge-like formation that is concentric with the outer rim. It is in the southern part where the rim dips down to its lowest portion, and a gap appears at the most southern point. The rim varies in height from as little as 200 meters to as high as 2.5 kilometers above the surface. The floor has numerous hummocks and rough spots. There is also a system of rilles that criss-crosses the floor, named the Rimae Gassendi. The fresh crater Gassendi A is adjacent to Gassendi to the north.” (https://en.wikipedia.org/wiki/Gassendi_(crater))

The rilles, in particular, could not be seen with 6mm eyepiece but became visible with 3mm eyepiece (6mm+2xBarlow). We weren’t going to stop until we saw those – so were very pleased with ourselves when we got them!

The main issue with 3mm eyepieces (6mm+2xBarlow) was that (even though the Ethos has 100 degree AFOV) the image shot across the field of view, giving little time to take it in before we needed to nudge the scope – the main failing of a Dobsonian telescope in my view.

From Gassendi, we dropped down to Copernicus, and thence to the Sinus Iridum, which stretches from the east at Cape Laplace to Cape Heraclides on the west. This required the 6mm eyepiece before we could start to see detail in the mountains around the edge of the sinus. What a view! Incredible! So beautiful and full of wonder. We could also see ghost craters within it, and this led to a discussion between us on the history of the moon, when one crater forms, gets filled with lava and then new craters occur within the same area without lava filling them.

Andy

Sharpless objects

This is a group of Sharpless objects: sh2-254, 255, 256, 257, 258, and 259

Still no PHD so again this is 2minutes x 23 unguided in Ha.

Just to guide you through, 254 is the largest nebula on the top. 257 is the next one down. 256 is the small one on the right of 257, and 255 is the lowest of the main group. Now for the difficult ones. 258 is very faint and small just below 255, by the width of 255 (on the left of two small adjacent stars). 259 is to the right of the main nebula 254 just above two bright stars near the edge of the image and again is faint.

Geoff