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NGC 5907 Splinter in the Dragon

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#1 frank5817

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Posted 30 June 2009 - 01:16 AM


When you live in a bright sky zone and can’t get away to a dark site, it may yet be worth your while to track down brighter galaxies if the transparency is good. This is what happened to me on Friday evening when I spent about 6 hours enjoying a warm dry summer night under the stars.
After a couple of hours of viewing bright galaxies, I remembered attempting to sketch NGC 5907 in late spring when clouds rolled in at put an end to observing. I returned to that edge–on galaxy on this evening and after getting as dark adapted as possible and moving the scope back and forth to stimulate averted vision, this is what I sketched. I did detect some irregular condensations of brightness in this galaxy.
This galaxy is about 39 million light years from us and although nearly edge on does not seem to have much of a central bulge. At low power it is a couple of fields of view to the east of the brighter lenticular galaxy NGC 5866 which is also nearly edge-on. NGC 5907 glows at magnitude 10.3 and is located at R.A. 15h 16', Dec. +56° 20'. I need about 10 inches of aperture to just detect this galaxy against the sky background on a good night.
In 1788 William Herschel located and described this nebula [galaxy].

Sketching:

(NGC 5907)
Date and Time: 6-27-2009, 4:00-4:25 UT
Scope: 18” f/5 Dobsonian. 28mm, 24 mm eyepieces 82x, 95x
8”x12” white sketching paper, 2H, 4H graphite pencils,
blending stump, scanned and inverted
Seeing: Pickering 8/10
Transparency: Average 4.5/5
Faintest stars visible overhead 4.4
Temperature: 26°C (80°F)
Galaxy magnitude: 10.3
Distance: 39 mly
Location: R.A. 15h 16m
Dec. +56° 20'


Frank McCabe :)

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#2 starquake

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Posted 30 June 2009 - 02:02 AM

Great sketch Frank! The splinter is one of my favourite galaxies. It's just so thin! I guess you've already seen NGC 4244 in CVn, which I found to look very similar to the Splinter. Some catalogues claim that it's brighter than NGC 5907, but I think it's fainter by at least 1 magnitude, and somewhat smaller in size.

#3 frank5817

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Posted 30 June 2009 - 10:22 AM

Ferenc,

Thanks, I agree with you about NGC 4244, it looks a little fainter than n 5907 although it is closer to us.
Most observers would not bother looking for galaxies under my sky conditions. No hint of the milky way is ever visible from my back yard. It is usually worth the effort to try for any deep sky object under less than ideal conditions. Sometimes a pleasant surprise occurs.

Frank :)

#4 rolandlinda3

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Posted 30 June 2009 - 11:58 AM

Great target and sketch, Frank. Don't think I have ever seen it or have forgotten than I did. I enjoy edge-ons so will add it to my list to see if astro video can pull out some detail.

#5 kraterkid

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Posted 30 June 2009 - 12:24 PM

Beautiful sketch and very interesting report on this intriguing edge-on galaxy Frank! :bow: :bow: :bow: You've done a wonderful job rendering the detail near the core. This sketch should serve as an example of what is possible even for folks who live in light polluted locations. Excellent job! :waytogo:

#6 frank5817

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Posted 30 June 2009 - 01:11 PM

Roland and Rich,

Thank you both for your comments guys. :thanx:
---
Roland,
This galaxy will look nice on your monitor and is still well placed after dark.
--
Rich,
The air here is frequently above 60% humidity. When it falls low the light scatter also drops off and it is surprising what galaxies become visible. With filters most of the brighter planetaries and emission nebulae are easily seen. So yes it is possible to do deep sky visually from poor skies. The dry air helps too.

Frank :)

#7 markseibold

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Posted 30 June 2009 - 01:19 PM

Frank

Excellent sketch of this edge-on galaxy :bow: :bow: :bow: and I agree with Rich; you have provided others with a great example of encouragement to observe even though we may think the light pollution will inhibit us. This galaxy is also one of John Dobson's favorites.

You have also inspired me once again to consider taking my 10.1" Dobsonian to a favorite location that many astronomers drive to only 30 minutes out of town. [I used to live only 18 minutes from that 4,000 foot mountain top for nearly 30 years.] Unfortunately the moon is waxing now. :foreheadslap: :question: :tonofbricks:

Mark

#8 rodelaet

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Posted 30 June 2009 - 05:01 PM

Frank,

Splendid sketch! :bow: :bow: :bow:

That was time well spent!!!

Wonderful fact that your could use all your observing techniques on this fine target. :pulpdnc:


A little query just learned me that about 320 deep-sky objects (above -40°) are brighter (in total and surface brightness!) than the Splinter, Frank. :shocked:

Do I see a small project for bright sky observers? :question:

#9 frank5817

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Posted 30 June 2009 - 07:23 PM

Mark and Rony,

Thank you both for the nice words. :thanx:
---
Mark,
I think about John Dobson nearly every time I observe. He more than anyone made it possible for many including myself to think it possible to build a telescope from scratch of large enough aperture to actually see deep-sky objects like this galaxy well. His contributions to amateur telescope making are enormous.
----
Rony, That is an interesting statement you make about all those (320) deep-sky targets brighter than NGC 5907. As much as I enjoy the challenge of trying to find galaxies from home; it is a lot more exciting to do this under dark skies as you well know. That would be a good project for a younger observer from a light polluted environment.

Frank :)

#10 Tommy5

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Posted 30 June 2009 - 09:15 PM

Very nice sketch of this edge on galaxy, great find from not so dark skies.

#11 frank5817

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Posted 30 June 2009 - 10:58 PM

Tommy5,

Thank you.:thanx: Hope you get a chance this summer to get away to a dark sky site for some observing.

Frank :)

#12 Tom Machtemes

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Posted 01 July 2009 - 11:57 AM

Frank,

Nice sketch, but did you get eaten up bu the mosquitoes. :question:

:thanx:,

Tom

#13 rodelaet

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Posted 01 July 2009 - 12:16 PM

As much as I enjoy the challenge of trying to find galaxies from home; it is a lot more exciting to do this under dark skies as you well know. That would be a good project for a younger observer from a light polluted environment.



That's right, but how many amateurs don't face the same light pollution as you do, Frank! They all would be amazed by what you achieve from your backyard. Your backyard observations are messages of hope for many others! :bow:

#14 frank5817

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Posted 01 July 2009 - 02:20 PM

Tom and Rony,
---
Tom, Thank you. The mosquitoes here have not been too bad when twilight ends. I keep a small piece of cloth in my shirt pocket with a few drops of DEET on it. That usually keeps them away.
---
Rony,

You really are a very positive person. No wonder you sketch so well. I think the stars enjoy being sketched by you. :cool:

Frank :)

#15 CarlosEH

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Posted 01 July 2009 - 06:48 PM

Frank,

An excellent observation of NGC 5907 in Draco. In reviewing this edge-on galaxy I learned that a "star stream" is visible in images obtained with larger instruments which are the remains of a dwarf galaxy that was torn apart ("cannibalized") by the larger galaxy (NGC 5907). Thank you for sharing it with us all.

Links;
http://www.hawastsoc...ps/dra/dra4.gif
http://www.noao.edu/...vers/n5907.html
http://apod.nasa.gov...d/ap080619.html
http://www.cosmotogr...ng_ngc5907.html

Carlos

#16 frank5817

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Posted 01 July 2009 - 08:22 PM

Carlos,

Thank you.:thanx: You always have interesting links to add. Thank you for these; they are always informative. In that great picture posted on APOD last year you can clearly see the potato chip warping of the outer visible disc of the galaxy.

Frank :)

#17 Michael11

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Posted 03 July 2009 - 02:20 AM

That's a very nice and realistic looking sketch of ngc5907,
I observed and sketched it few weeks ago (I'll post it a little bit later), under dark desert skies. It actually was quite easy to detect in 8" newtonian, and I really liked it's thin elongated structure

#18 frank5817

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Posted 03 July 2009 - 10:10 AM

Michael,

Thanks for your kind comment. It really is a very fine target from a dark site. It would be nice to see sketch of this galaxy from the desert sky.

Frank :)






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