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10 Aug - Big dob enjoys a nebula marathon and sees an Angel (Night Vision)


alanjgreen

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Date: Friday 10th August 2230-0245
Scope: 20” f3.6 Lukehurst Dob with Paracorr (fl = 2089mm & f4.1). Night Vision: PVS-14 with Photonis 4g INTENS.
Eyepieces: 55mm (f2 x38), 27mm (f4 x77)
Filters: Astronomik 6nm Ha CCD
Moon: 0%

 

Before we get started

This is a long report. I will mark the most interesting stuff with underline should you wish to scan it and just digest the meaty parts…

 

It’s clear and dark!

I head outside just after 10pm and get the big scope setup & check collimation (all ok).
I have a plan to continue to view nebula using Sky Safari 5 (wifi connected to my Nexus) and have a marked up copy of “Astrophotography Sky Atlas” by Bracken on the desk ready…

 

Start with some brighter stuff, its still early…

With the roof pushed back and two-star alignment completed, I head for Gamma Cygni (IC1318a, b & c) There seems to be a mismatch between Bracken and Sky Safari where Sky Safari has the IC1318 labelled a, b, c top to bottom but Bracken labels the top nebula as IC1318b?

I added the Astronomik 6nmHa CCD filter to the Paracorr2 and inserted the 55mm Plossl then attached the PVS-14 NVD to the Plossl.

The views were wonderful! (even without full darkness), the nebula was showing as bellowing white clouds with real texture, occasional black patches and lanes could be seen within the lush whiteness. I took my time and nudged around finding myself first of all bumping into the huge bright Crescent nebula at one end and the fainter but intriguing Pelican at the other end.

IC1318a – I specifically targeted the “a” top section and was rewarded with a lovely bright “dagger” shaped nebula. There were black patches seen within the varying brightness shape and I had to nudge around to see the whole thing.

NGC6914 – I moved across to the nebula NGC6914 closeby and saw lovely lanes of nebula in all directions. There were some very bright areas within this nebula. A real treasure! :)

Propeller – Next up, the Propeller which was easily seen as an “S”, with a bit of time at the eyepiece the other cross sections came into view. Maybe it was still a little early to see it at its best but I forgot to come back later.

Veil – Onto the Veil and it was a sight to behold, equal to my best ever viewing of the other night. The western section was showing the split at the top into three parts (so I knew it was going to be good). I traced my way around the now familiar parts of this huge complex. For the first time I noticed that the lower western section has a “broken claw” shape within it (just below the bright star). The other highlight was seeing two intertwining strands of nebula along “the thin thread” section, like someone was twisting two wires into a twisted-pair. I noted wonderful bright details and outlines in the eastern veil and enjoyed the holes and knots within Pickering’s triangle. :)

Sh2-128 – Its getting visible darker now so onto some Sharpless. Sh2-128 was seen as a very small patch but easily seen.

Sh2-127 – slightly larger “double patch” but fainter than sh2-128

IC1396 Elephant trunk – I have visited this a lot recently, but tonight it was later and darker than previously this week. I was rewarded with superb white nebula and easily spotted black patches of varying shapes and size. The centre elephant truck was lovely and sharp, the outer trunk has less defined edges and I worked to see a right angle notch in the corner of the nebula for the first time. :)

NGC6946 Fireworks glx – After my success of getting the arms on the previous night, I had to come back for another look. This time I found the arms harder to see. I got them with averted vision but I don’t remember it being as hard the night before? Although I did note a faint showing of the third small arm underneath as what seemed like two small globular like patches pointed the way.

Wizard – Up next, the wizard. I picked out the “horse” and “camel’s back” and the brighter areas noted on previous visits.

Bubble The bubble was really good. It was surrounded by a larger, fainter nebula structure not seen the previous night. It really is quite a large area. The bubble was round and bright with the central brighter section really shining brightly. Really enjoyable. :)

Sh2-159 – uneventful blob of nebula.

Sh2-158Nice. Double circle of nebula. Two stars peeping through and very bright section to the left hand side. Also confirmed that Sky Safari has this area as blank – it labels the area around “sh2-159” as “sh2-158”!

M52 cluster – bumped into this lovely tight cluster as I roamed around this area of sky.

Sh2-170 – Large textured nebula patch. Two stars in the central blackness.

NGC7822/sh2-171After resolving some confusion as to what was sh2-171 (it’s the same as NGC7822), I found a thick lane of nebula with a bend in it. Bracken describes it as “Cosmic Question Mark). Up close in the dob then the question mark was not really how I would describe it (but I did some x1 NVD viewing later and IT IS more like a question mark at very low magnification). Nice bright nebula. :)

CED214 A real treat but seemed much smaller than on my last visit. Lovely 3D texture and varying white/grey/black colors. Looked like a “fist and knuckle duster” to me.

IC63 – Right angled corner of bright nebula. Small. (Bright star nearby causing reflections so would ideally need more magnification to get it out of the fov).

IC59 – Right next door in same fov. Straight thick patch of nebula. (Same star reflection problems as above).

Sh2-173 – Decent sized nebula patch with a big hole in the centre. On images this morning, it looks like a “mask”. I did not note that so I now I will have to return for another look…! :)

Sh2-175 – tiny nebula patch around a star.

Pacman This was the highlight of the night for me. First time that I have managed to get the whole of the big mirror onto the target (shed walls reducing aperture on previous attempts this year). Wowsers! It looks absolutely nothing like the view through traditional eyepieces with the 20”. I saw an “angel” not a “pac-man”. A white, textured angel shape, there was a black cactus under the left arm. Cactus splits off with a small side branch. Two small black holes seen in the whiteness. I held the sky safari image to the side of the eyepiece and did a side-by-side comparison. Lovely. :) :)

Sh2-132 – bright arrowhead shape. Two black lanes cut into it. There were two small brighter sections, one left side and horizontal and one right side and vertical direction.

Sh2-135 – small space triangle.

Sh2-157One of my favourites, a very large “heart” or “space squid” with an extra bright small circular patch within it. It has lovely outer edge detail all around. There was an extra small line piece of nebula out to one side. :)

Sh2-158 – small patch just to the side of sh2-157

Sh2-163 – small faint patch

Sh2-166 – small even fainter patch

Sh2-168Triangle of stars shaped like a “segment” overlayed with a semi-circle of larger nebula on top. Very bright central area. Great. Images this morning do not reflect what I saw. The prominent “segment” does not come through on images. There is some black gas coming into one side, this must be part of the segment? :)

Cave – I bumped into the Cave by chance and it was looking great against this dark sky. Better view than on previous nights this week. The black cave section stood out well against the surrounding nebula. The leading edge like a tidal wave pushing through the sky.

 

Galaxy Comparison

I removed the Ha filter and headed for my first NVD viewings of Andromeda and accompanying companions. I began by switching to the Ethos10 and removing the NVD to get some views to compare against. M31 was great in the E10, with the two black lanes extending well out into space.

 

M31, 32, 110 – The central part of M31 was really sharp in the 55mm Plossl and NVD. The core was a lovely bright circle. The two black lanes were really sharp as they passed though the bright central dust. As the lanes moved out into space they became harder to trace than with the E10 previously. M32 and M110 were both clear and sharper with NV. M110 was larger with the E10.

NGC147 & NGC185 glx – Another side by side comparison yielded similar results to M110. I found them larger in the E10 (but I was using x200 magnification) yet they were just the same patches in the sky with the NVD (yet only at x38). Hard to say which was best. They certainly had more contrast and were easier to hold with the eye with NVD. But I was starting to get tired by now.

Stephans Quintet – Onto one of my favourite night sky objects. With the E10, I saw the central triangle of galaxies and centred the group. There was another galaxy close-by. I do not remember seeing both cores in the merging galaxy (which I have seen before with big dob). With the 55mm Plossl and the NVD the quintet are obvious (at x38 magnification), NGC7331 appears in the same fov. I nudged them central and one of the central triangle of galaxies is missing, there was a central two galaxies.  I could see 4 galaxies in the area, one was next to a star. I need to come back when I am more awake and repeat this exercise once again.

Interestingly, when I centred NGC7331 I could pick out the same 4 flea galaxies to the side at x38 magnification that I saw with the E10 at x200 (mind boggling).

 

Box kite in the Sky

M76 In the area I saw M76 and nudged over. I am glad I did! What a surprise. I was expecting a mini dumbbell and instead got a “box kite in a circle”. The box kite had a white box at either end with a larger central black oblong shape. The whole thing appeared to be within a circular structure. At x38 it was very small to the eye. The view did not resemble anything I have seen with traditional eyepieces. Another one to revisit with more magnification on another night. :)

 

Tiredness gets us all in the end!

By now I was really tired and decided to close up the shed and grab some x1 milky way views by attaching a 1.25” 12nm Astronomik Ha filter to the front of the NVD. It was 0230, so I had managed 4 hours and the list of targets had been huge. I have not mentioned many old friends that I happened upon during the night, just those that made it into my notes.

x1filter.jpg.20f3fe2546c6279127dba93ff8317c50.jpg

 

The wonders of x1 with NVD and Ha filter

I scanned the sky holding the NVD direct to my eye and looking up. I focused the NVD by turning the front objecting using the Seven Sisters as my target. Bang! There’s a big log of nebula next to the Pleiades (California), Boom! There a multi patched nebula coming up over my neighbour’s house, looks like a flying bird (IC410 & Flaming Star). Moving up a nice pair of nebula (Heart & Soul). Into Cassiopeia and several smaller blobs of Nebula (maybe Pacman). Keep moving, and there is the IC1396 Elephant trunk (some black detail within), onwards to very bright North American and Pelican next door. Into, Cygnus and very bright detailed blobs around Gamma Cygni.
The main drawback of x1 is the wear and tear on your neck!

 

Dawn is not breaking

It was 0245 when I made my way back inside and looking up the Milky Way was still clear and wide. The black streak between the two arms still looks really black and stands out lovely against the sky. Only a month ago the Sun was forcing me inside at 0200 and now it’s nowhere to be seen… Seems the astronomy window is opening once again and I am a happy man!

 

Clear Skies, Alan

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Brilliant, hope there’s something of challenge left in Bracken! 1x is always fun to see all the big stuff that is right there... you wait till Mr Orion comes around, then you’ll know what “big nebula” means!

have you started “nebula hopping” to find stuff yet, or are you just  Go..ing To?

PEter

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1 hour ago, PeterW said:

Brilliant, hope there’s something of challenge left in Bracken! 1x is always fun to see all the big stuff that is right there... you wait till Mr Orion comes around, then you’ll know what “big nebula” means!

have you started “nebula hopping” to find stuff yet, or are you just  Go..ing To?

PEter

Yep, started nebula hopping :)  (the big ones anyway). Like navigating around a city in the sky...

 

As for a "challenge", the Iris and various dark nebula have proved elusive...

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For a challenge I suggest the witchhead... a reflection nebula that should be invisible to NV. Never had much luck with dark nebulae, though not had much time under good enough skies and so don’t have an eye for what I am looking for. However saw some nice milky way mottling around scutum a few nights ago with the 680nm, sweeping about to help “mentally average” things. Want to try that again.

Peter

Ps I have a friend who said what he saw for that dark Neb and it’s sadly not printable!

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Huge report to compliment a huge telescope!  I’m amazed how low the focal ratio is on these monsters.  Excellent read and I’m envious of your skies. The Milky Way is hard to come by over here in NELM 5.5.  I’ve tried for some of those targets like Heart and Soul but have only had a sniff.  Clear skies

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2 hours ago, Special K said:

Huge report to compliment a huge telescope!  I’m amazed how low the focal ratio is on these monsters.  Excellent read and I’m envious of your skies. The Milky Way is hard to come by over here in NELM 5.5.  I’ve tried for some of those targets like Heart and Soul but have only had a sniff.  Clear skies

With the focal ratio of f3.6, it means I can stand with my feet on the ground and still use the scope straight up at the zenith.

This was a prime requirement for my dob purchase as I refuse to stand on any steps in the dark! Better to spend an extra £500 than risk breaking your neck or worse, the scope!

With the Night Vision device attached to the 55mm Plossl and all the extra out focus that needs its already a bit of a "reach" to grab and nudge the scope to the next target.

Besides the lack of any need for steps, the best thing I ever did was get the encoders and Nexus wifi added to the scope. As you can see above, the targets just keep on coming when you can see where you are pointing :) 

David Lukehurst was happy to install all these bits and bobs onto the scope as part of the build process so for me, very little extra effort was involved except the cost.

To me, it's the greatest scope in the world. 

BUT if I had to assemble it every night (rather than just open the shed) then I would likely have broken something by now as well as needing someone else to help me assemble and disassemble it.

As far as my great skies, we moved here specifically for the dark skies. At the end of the day it's the only real option. If you get the chance to move out into the country then take it, you only live once :) and once your kids have moved on then why not?

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I agree about the 2person. I once had to help a chap who Big Dob got blown round and bent the encoders. He’d never lifted the rocker off the base ever. With some duct tape/multitool action we had him on the way in time to continue observing.

PEter

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