17 July - Big Dob uses Night Vision to BLOW THE BUBBLE

[alanjgreen]

Date: Tuesday 17^th July. 2320-0150       

Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS.

Eyepieces: 55mm (f2 x38), 35mm (f3 x60), 27mm (f4 x77).

Filters: Astronomik 6nm & 12nm Ha CCD.

 

It’s a CRAZY world!

According to my notes, my last time out with Big Dob was 17^th May! That’s a whole two months of “resting” for the big scope. In the meantime, I have been out for regular sessions with my Borg frac on the planets and of course on Nebula with the aid of my night vision, but still I was not expecting it to be two months of a gap. It also explains why it was hard to remember all my well-rehearsed setup steps for collimation etc. I had to seek out the Paracorr2 in a cupboard as it was not even in my eyepiece box.

 

Preparation as always is key…

I had been out in the shed earlier in the week and had re-positioned big dob into one corner so I could get a clear shot at Cygnus and the Milky way. I set out early just after 2300hrs as I wanted time to collimate and had more kit to carry down the garden than usual…

As it turned out collimation was a breeze, just one screw on the primary needed half a turn.

I was soon setup with the roof rolled back and Nexus 2-star alignment completed.

 

Some early targets… but it’s not dark yet!

I replaced my alignment 10mm eyepiece with the 35mm Panoptic and attached the PVS-14 Night Vision Device (NVD). I started with a quick tour of some well-known targets to get my eye in, with the intention of coming back to them once again later when it was darker (Ho Ho Ho).

Fireworks glx - I centred the Fireworks galaxy using the push-to and Sky Safari. The galaxy appeared as a faint decent sized patch. No arms were seen.

Comet 21p Giacobini-Zimmer – A very easy target. Comet had a bright good sized core with some surrounding fainter dust cloud.

North American & Pelican – I added my recently acquired 12nm Ha CCD filter and moved to the North American. These big targets are much harder to get oriented on than when using the wide-field Borg. At x60 it was just so big that I did not get the same overall viewing experience as when I can see the whole thing. The Pelican was good though , there was plenty of intricate detail available in the beak section that you just don’t get when “zoomed out”.

Elephant trunk – Not a lot to see here

Cocoon – The Cocoon was great (even before dark), I could see the whole thing and it was easily compared to the image (on Sky Safari), the “whole thing” was visible.

Cave – The Cave was easily located and the bright frontal section was seen in direct vision. The outer parts were fainter but the cave section was very black.

Bubble – Onto a target that the Borg cannot handle. At first I struggled to orientate myself to what I was seeing. I could see a bright star with a bright “comma” shaped small nebula piece next to it. Time at the eyepiece seemed to reveal a small “black circle/hole”. I persisted…

 

Time to BLOW THE BUBBLE!

Midnight, now it’s getting a bit darker… I could sense that the sky was finally getting a bit darker and the Bubble is a target that I have never seen so I stayed and played with combinations of eyepieces and Ha filters.

27mm Panoptic & 6nm Ha filter – Wow, what a difference! As soon as I threw in the 6nm filter the Bubble Nebula trebled in size. Two large patches of nebula appeared under the two stars. The circle of the bubble appeared (or so I thought at the time!)...

55mm Plossl & 6nm filter – With the increased speed offered by using the 55mm Plossl, the whole Bubble nebula appeared. There was now  a long upper section reaching out towards a third star. I began to realize that I had oriented myself incorrectly and the two stars I thought were the Bubble stars were in fact not them. The second star was further away and the scale of the object was much larger than I had anticipated! As I turned down the gain on the NVD, the bubble appeared and it was BIG. I held the image from Sky Safari in my hand to the side of the eyepiece and finally got the two to match. Literally, I could see “everything” that was in the image. Amazing, I smiled with satisfaction. Bubble Nebula = CHECK!

 

Feeling a little Sharpless…

I enabled my Sharpless observing list in Sky Safari. The area around the Bubble was littered with Sh2 objects. Time to get some of those smaller ones into the eyepiece. I had the 55mm Plossl and 6nm Ha CCD filter loaded.

Sh2-157 – Beautiful large shape that had to be nudged to see the whole thing. It really looked like a “Heart”. There was a small bright blob seen inside the upper part of the “heart”. The uneventful patch shown in sky safari did not do justice at all to this fantastically detailed nebula. I encourage everyone to google an image of this nebula – it’s wonderful!

Sh2-158 – Small and very bright nebula. Left side brightest part then two looping block sections. It looked like a face lying on its side. Great.

Sh2-163, sh2-165, sh2-166 – Faint patchy stuff.

Sh2-168 – Small bright patch with some lovely detail in its structure. Nice.

Sh2-152 & sh2-153 – I decided that this was a “whale and child”. There was a very bright little “baby” next to a much fainter and larger “mother” patch. Nice.  

Sh2-149 – Bright little patch of nebula.

Sh2-146 – Less bright little patch.

Sh2-132 – Wow, large bright patch with shape and structure. Seemed to look like a “bat”. Very nice nebula.

Elephant trunk – Now it’s darker, it’s time to revisit the Elephant trunk and see if I can see it? Wow, it’s just so big and bright too. I nudge around and see lovely black lanes and then yes, the elephant trunk is big and clear. I get a picture up to view on Sky Safari and orientate myself by turning the iPad on its side. Now the view and the image match. I nudge around and tick off each and every black patch and lane seen in the image. The trunk section near the centre is eye-wateringly beautiful. The second outer trunk section is a bit less defined around the edges but I am now a very happy man. It is literally just like an image! 

Sh2-129 – Another lovely nebula. It appears as a bright traceable curve. Very large. Looking at images on the internet this morning, this seems due another visit in August when darkness returns!

Sh2-126 – Another good one. A very long faint line of nebulosity. Requires plenty of nudging.

Cocoon – Time to revisit some old favourites. Wow. The Cocoon is framed beautifully in the 55mm and it just like an image. I compare to Sky Safari and I can see it all easy and in direct vision!

Bubble – Had to go back to the highlight of the night for a second viewing now its darker. Fantastic. With the gain turned down a bit the bubble is clear and black.

IC1470 – Tiny elongated bright blob. A bit like a planetary nebula.

Cave – 55mm & 6nm Ha gives the best view. Its like a tsunami washing across the sky. The leading edge is wide and bright. Lovely.

 

<CLOUDS ROLL IN>

 

Thoughts from the observer

As you wander through the Sharpless objects, it’s amazing how BRIGHT some of them appear, much brighter in fact than some of the well-known and better labelled objects. It just seems amazing that we found them hard to find and see. With a narrowband Ha CCD filter these objects come to life and form a seemingly never ending list of nebula to astound us with their beauty.

I thought I had “seen it all” of the summer objects but NVD is opening up a whole new world of objects to see and with a list this LONG, it’s going to take me several summers to get through them all.

Please do google some of these wonderful objects and get a flavour of the night sky we have been missing all these years…

 

Clear Skies,

Alan

[Tim]

Great report Alan, very intrigued by the NVD, any chance you could post a pic of it attached to an eyepiece?  Thanks!

[alanjgreen]

36 minutes ago, Tim said:

Great report Alan, very intrigued by the NVD, any chance you could post a pic of it attached to an eyepiece?  Thanks!

 

[Rob]

Nice read indeed. The NVD sounds & looks a great piece of kit. Where did you source it?.

 

Regards Rob

[Paz]

Great post, this kind of observing is completely out of my league but is exciting to read about.

[alanjgreen]

1 hour ago, Rob said:

Nice read indeed. The NVD sounds & looks a great piece of kit. Where did you source it?.

 

Regards Rob

I puchased it from ActinBlack (Luxembourg). Much more info for you in these posts

 

HTH, Alan

[Rob]

Thanks Alan..

[Eastman]

Great report Alan, nice nebulae. Must have been great to get out with that 20" after 2 months.

[PeterW]

Have to see which of those I have tracked down... Cepheus is my second favourite area after Cygnus (as never get much chance on Sagittarius). Surprised yoh didn’t point it at NGC7822&Ced214, maybe too big for the 20”.

Cracking report 

PEter

[PeterW]

Really nailing the smaller Sharpless with that setup. Good to see you’ve nabbed sh126, picked it up on a dark trip last year. Looking forward to more reports.

 

peter