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Norman
March 29th, 2016, 01:58 PM
Hi folks!

I finally want to present one of my observing nights in the german alps/ bavarian mountains. I hope my english it not too painful for you. If u do not understand anything what i wrote or something sounds exceptionally awful – feel free to aks/ correct me :-))

Following the report of my last very good night with my 12“ f/5 travel dobsonian:

(The longer report in german you can find here (brauneck allnighty):

http://www.astromerk.de/downloads/category/5-berichte.html)


Almost exactly to new moon from Dec the 10 to December the 11th 2015 the forecasts in the mountains have been breathtaking: air humidity: lower than 20% and inversion with temperatures above zero meanwhile in the valleys below zero... Unfortunately my favorite observing site at the „Wendelstein“ with its 6000 feet above sea.leval was not within reach – recent snowfall made it too dangerous to reach.
So my alternative was the „Brauneck“-mountain at 5000 feet above sea-level – a very popular mountain in bavaria with lots of tourists. Not the first choice to have a calm night … But i have been lucky: exactly this very night the shelter at the top was closed because the service stuff had some kind of meeting next day in the valley. I got to knew this when i called the people from the „Brauneckhaus“ in order to book a night to sleep – as backup when night turns very bad. So i had the terrace alone for me and my Telescope!

The night was hard to estimate with regard to clearness. High clowds have been predicted – but the exact time was uncertain. Worst case they would came right after sunset – best case in the morning. I just dared and risked everything. The starless nights just have been far too many to let this chance go.

I shorten the prelude a bit – i am wellknown for my long writing ;-) So i reached the mountain by railtrain without complications – a snowwhite landscape and above a very blue clear sky and dazzling sun. Some folks wished „nice flight!“ to me – a common mistaking lookin at me with my bigbig bagback – equal to that of the paragliders that use to jump from that mountain. Last guests came out of the shelter that would close soon – a group of men – business trip or somethin – all of them have been joking around – threw with snowballs... „what a damned bad weather!“ one of them was joking – in short: they have been in exactly the same mood as me – just awfully happy because of this great view into the mountains under that beautiful sky, that freedom.

The little house where i planned to stay the night was equiped with motiontrackers. That would let light switch on as soon as i crouch down to my starchart or eyepiece-case. I covered that with a handkerchief – also a emergency-Exit-light shining out of a window enlighted the snow. So i attached my isolation-mattrass to the window – looked awful – worked well :-)

Soon fairly disturbing wind occured. Fortunately the entrance of the house was build that way, that it provides a windshield when placing beneath. Difficult to discribe – easy to see in the pic :-)
Boy – i was THAT happy to have that protection from wind! Otherwise night would have been painful.

2031

The objects

Since three years or so i am having a project – the superthin galaxies. Stathis Kafalis and Uwe Glahn from Germany filtered the original RFGC-list with its 4440 Objects: brighter than 16m0 und higher than -25 De – 133 objects remained. A wonderful project that catched me from the very beginning for many reasons. Most of these galaxies are quite faint – very low surface brightness and overall brightness mostly around 14-15 mag. So very good transparency is needed. I only try these galaxies when having that conditions. THIS night – was one of them. I already observed 69 of these galaxies successfully, in 8 cases i failed – but there was/ is a lot of work to do.

First object was UGC 11455 with 14m5: after short concentration easy to catch and to hold in my 8mm Ethos. Next one: UGC 11859 (15m2). A night before with equal good conditions i already tried – without success. I wrote in my report „only try again under very good conditions“. I didnt see this note when trying... Although culmination time was over since a while i succeeded: Around 30 minutes have been passing by... but then i catched position and position angle correctly – hard work at the eyepiece. What really helped for verification was the position angle. By that u can be sure not having „seen“ somethin else.
Next object is some exotic one: ESO 540-16 – very close to Deneb Kaitos, a star of second magnitude in Cetus. Despite of the low height and 14m5 it was easy to detect. Prominent feature: a foreground star from one of which the galaxy streak seems to come from – just like a laser sword or somethin ;-) A very nice object. Reflex free exepieces are very important here – my 12mm T4 Nagler showed a brutal glare although the 2mag-Star was out of the field. My 8 mm Ethos didnt. Have to check whether the chrome-barell is the reason or somethin within the eyepiece itself.

UGC 1999 with its 14m1 was next stop. Basically it should not be that hard – with a look at the Magnitude it is one of the brighter ones in the list....But nothing is more far away from truth than easyness! This gx was tough. Really tough. But i am not that sure if cirrus clouds could have disturbed the view – soon they came around just like predicted. Damned. But i already observed full 4 hours! Actually quite a fine issue – clouds could have been coming very much earlier...

What to do now? I thought about sketching some clusters but decided for somethin to eat instead. I sat down in the entrance zone of the little restaurant – where over day hundreds over hundreds of people are walking around. Funny stuff i thought for myself. An unbelievable nice place to sit and to relish the panoramic views from east to west: mountain tops from one side to the other, framed by the entrances housing. While i was chewing my bread, a tiny cute meteor underneath the belt of orion felt from the sky – ending up with short a orange toned flash. Time to get a wink of sleep i thought and slept away... app. one hour later i woke up – sky was clear and really alpin now!
I moved my hand over my mattrass – bluegrey sparks appeared – wow-what a low humidity! These conditions have to be used as good as possible.

2032


So i tried somethin hard: UGC 2092 (15m0). Although trying hard i failed. NGC 1886 in Lepus was next stop, in field of view together with globular M 79 at low power. Very very nice object! Although lower than -24 Dec easy to observe – in field with a prominent chain of 4 stars of equal brightness.

2033

Equally nice: NGC 1145 (14m2, - 18 Dec): wonderful galaxy! Also made a sketch of it.

2035

UGCA 145 was next one: although 14m3 and – 20 Dec easy to detect in full length: a very very long needle in comparison to other candidates in that list. Easy to detect means easy with averted vision of course and after some time of concentration. It does not pop into view!

To get some relaxation i took a glance onto M 51 – the later the night – the more dazzling that wheel of light – wow. Enough relaxation-such a sky – such chances – u got to stay tough!
I tried one of the nasties members out of that list: ESO 494-7 in Puppis: -24 54 Dec and 14m9. In the middle of the milky way. Why and how the hell this guy managed to be taken into that list? Damned again! Starfield was found easily – but galaxy itself – nope. In the backmost imagination i assumed there could be somethin.... but far away from status „seen“. Really sick objekt – just take a look at DSS...
Spontaneously i came across NGC 2424 – not far away from the globular „Intergalactic Wanderer“. This globular alone is a pleasure to look at – with the contrast to the two bright stars beneath.
One of my last objects was not a superthin but somethin alike: PGC 16636 in Orion (somethin around 15mag) – a thin galaxy not far away from the batnebula (at least its name in germany) NGC 1788. On DSS it shows a dustlane. Visually i just hardly detected the galaxy itself, a bit more thick than its superthin brothers.

The night did not want to end. A few times i thought „now dusk is coming“... again and again i was wrong... Unbelievable – 10 hours deepsky! A dream, just a crazy dream. Looking at my clock i was surprised: 7 o´clock! My favorite train would be leaving soon so i packed up everything and left.
I was able to see first sunlight yet – just beneath a prominent mountain – great timing! With dusk came cirrus clouds, as if they waited this time to apologize for several wasted nights... A signal of peace – thanks!

2036

2034

Clear skies!
Norman

KidOrion
March 29th, 2016, 03:14 PM
Great report and nice sketches, Norman! Looks like a fantastic site, too.

I'm working on the Astronomical League's Flat Galaxy observing program; I'll need to check how many of your targets here are on it. I'd have thought many of yours would be beyond range of my 12.5" scope, but I guess I was wrong. Thanks for posting this!

Norman
March 29th, 2016, 05:57 PM
Hi Kid, thank you very much for your kind reply :-)

Ahh - interesting program - haven´t heard about until now. I visited the page and checked the list of Appendix A there. Up to now i could detect 64 of these objects in my 12". So no problem for you to get the award by observing 50 :-) Transparent skies given of course...

I have to add: the selection by Uwe and Stathis also is filtered by major axis size: 2,5 arcmin - anything smaller is not in the list i am working with.

Do not be afraid of the low brightnesses - not all of the figures are correct. Add to this - the RFGC-Magnitudes are photometric brightnesses in the blue. So the visual brighness is often 1- 1,5 mag higher approximately, at least in my experience so far. Very helpful is the work of Wolfgang Steinicke, with all the correct brighnesses of NGC and IC-Objects (revised NGC/IC-Data): http://www.klima-luft.de/steinicke/ngcic/ngcic.htm

"I'll need to check how many of your targets here are on it" ... all 133... apart from very little differences: UGCA 320 (RA 11 49, - 17 29 Dec) e.g. is not in that Appendix-A-list. I don´t know why. All in all the lists are identical.

CS!
Norman

lamperti
March 30th, 2016, 02:41 PM
It is in Appendix-A though it it listed as "MCG-3-33-30" under "Other ID". Its RFGC # is correct as '2449'.

Al
(Flat Galaxy Observing Program Coordinator)


Ahh - interesting program - haven´t heard about until now. I visited the page and checked the list of Appendix A there. Up to now i could detect 64 of these objects in my 12". So no problem for you to get the award by observing 50 :-) Transparent skies given of course...

"I'll need to check how many of your targets here are on it" ... all 133... apart from very little differences: UGCA 320 (RA 11 49, - 17 29 Dec) e.g. is not in that Appendix-A-list. I don´t know why. All in all the lists are identical.

CS!
Norman[/QUOTE]

Norman
March 30th, 2016, 09:18 PM
Hello Al,

you are right - just checked again. This is one of the very few mistakes in my original excel-sheet. Already had a note on it (wrong coordinates, where actually is nothing) but didn´t see it recently in the column of my notes (very last column in wiiiiide excel sheet on a small notebook ;-).

So remaining differences between our tables just might concern galaxies with major size = 2,5 - not all of them are in my list whereas it is in yours.

greets
Norman

lamperti
March 30th, 2016, 09:43 PM
The Flat Galaxies were listed as long as they had a major axis to minor axis ratio of at least 7:1 and a diameter greater than 40 arc-seconds

Have fun with whatever you do!

Al

Norman
March 31st, 2016, 01:29 AM
Hello Al,


The Flat Galaxies were listed as long as they had a major axis to minor axis ratio of at least 7:1 and a diameter greater than 40 arc-seconds

Al

I know that of course. Just wanted to point out the filtering criteria (that had been applied to the RFGC) of the list i am working with.


Have fun with whatever you do!

Al

Thanks - i am doing so - it is really big fun hunting down these fine streaks :-)

BTW: nice to have you here as an expert for superthin galaxies! I am very interested, how many people already managed to observe 100 objects of Appendix B - you are having the overview of that don´t you? Furthermore - what was the smallest aperture 100 objects could have been observed successfully with?

What was your size of Scope when hunting down the 100 - your 22"-Dob :-)?

Greets and CS!
Norman

lamperti
March 31st, 2016, 01:14 PM
I don't know why my reply did not get posted, so I will try to repeat it:

27 observers have done 100 Flat Galaxies observations for the honorary certificate and 1 more earned a Regular certificate. I did all of mine with a 20" f5, the predecessor to the 22". A few people visually observed with a 12" and one other imaged with a 12".

I do not claim to be an expert on Flat Galaxies. I just combed the literature and put the program together for approval by the Astronomical League. You may also want to consider doing the Active Galactic Nuclei Program with your telescope. Some folks have imaged these with a 4" !

Al




I know that of course. Just wanted to point out the filtering criteria (that had been applied to the RFGC) of the list i am working with.



Thanks - i am doing so - it is really big fun hunting down these fine streaks :-)

BTW: nice to have you here as an expert for superthin galaxies! I am very interested, how many people already managed to observe 100 objects of Appendix B - you are having the overview of that don´t you? Furthermore - what was the smallest aperture 100 objects could have been observed successfully with?

What was your size of Scope when hunting down the 100 - your 22"-Dob :-)?

Greets and CS!
Norman[/QUOTE]

Norman
April 1st, 2016, 11:57 AM
Hello Al,

thanks for the figures. Funny, only one with regular certificate... all or nothing seems to be the guideline ;-)

Very interesting that already several people managed this project with "only" 12". Nice encouragement for all those out there, who are afraid of supposed weaknesses in overall brightness with medium to small sized instruments.

C S!
Norman

Jim Chandler
April 1st, 2016, 12:36 PM
I am very interested, how many people already managed to observe 100 objects of Appendix B - you are having the overview of that don´t you? Furthermore - what was the smallest aperture 100 objects could have been observed successfully with?

Norman

I don't the minimum aperture necessary to view 100 superthins, but back when my wife was doing the research that evolved into the 2010 Texas Star Party Advanced Observing List, she observed over 250 with an 18" f/4.5.