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Saturn Nebula NGC 7009

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#1 frank5817

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Posted 26 August 2009 - 09:48 AM


This planetary nebula was one of the first “nebulae” seen and recorded by William Herschel during the summer of 1782.
Since my skies are loaded with sky glow, it is not possible to see the ansae (handles) at the ends of the long axis of this beautiful bluish planetary nebula. With the ansae visible this planetary nebula very much resembles a blue version of the planet Saturn with its rings edge on. At high magnification the white dwarf central star is easily detectable with 18” of aperture although the view is much better under dark transparent skies.

Sketching:

NGC 7009 Saturn Nebula (planetary)
Date and Time: 8-25-2009, 4:15 4:50 UT
Scope: 18” f/5 Dobsonian. 24 mm eyepiece 95x
8”x12” white sketching paper, 2H, HB, graphite pencils, light brown color pencil,
blending stump, scanned and inverted
Seeing: Pickering 7/10
Transparency: Average 3/5
Faintest stars visible overhead 4.3
Temperature: 20°C (68°F)
Nebula magnitude: 8.0, Central star 11.5
Distance: 2000-4000 ly
Location Constellation: Aquarius
Position: R.A. 21 hrs 4 min
Dec. -11° 22'

Frank McCabe :)

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#2 Aldebaran

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Posted 26 August 2009 - 10:13 AM

Good work, Frank! Nice observation and report!

#3 kraterkid

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Posted 26 August 2009 - 10:22 AM

Excellent sketch and report Frank! :bow: :rainbow: :bow: Especially impressive because you captured this beauty in a fairly light polluted area. :waytogo:

#4 Jef De Wit

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Posted 26 August 2009 - 02:14 PM

Frank, nice sketch. I observed the nebula the 3th of this month with my 30 cm Dobson, also in suburban region with the Moon in the sky (NELM 4). But I din't see at x171 the "ring" or the central star. I noticed some green (and not blue).

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#5 Tommy5

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Posted 26 August 2009 - 05:09 PM

Very cool sketches Jef and Frank i have never seen this nebula but now i feel as if i have thanks for sharing.

#6 frank5817

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Posted 26 August 2009 - 05:49 PM

Juha,Rich,Jef,and Tommy5,

Thank you all for your comments. :thanx:

I was back and forth with an ultrablock nebula filter which I did not attach to the eyepiece. I was using the filter to get the shape. With the filter this nebula looks greener and without the filter it looks more like an aqua blue to my eye. I see the "cat's eye" NGC 6543 as a green with or without a filter. With both of these planetaries I have no trouble with the central star unless I use a filter then the star is not visible.
Jef, very nice sketch of NGC 7009 and in your sketch on my monitor your nebula looks more blue than green to my eyes. Maybe I have a fundamental problem with my colors? I chose a light brown color pencil for this sketch because inverted it was the closest color to what I saw at the eyepiece.

Frank :)

#7 JayinUT

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Posted 26 August 2009 - 11:47 PM

Frank,

I love your capture of this fun planetary. I haven't looked at it in over a year now so perhaps tomorrow night I will have to sneak a peak and a new sketch.

I agree on the central star, not to hard to observe unless one leaves the filter on. I use an ultrablock also and I also see a more greener look on this one.

The Hubble Image has always reminded me of a piece of wrapped up salt water taffy.

#8 frank5817

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Posted 27 August 2009 - 08:08 AM

Jay,

Thank you for your comments. :thanx: Like you I examine this planetary about one time per year. My sky is so light polluted I usually wait for this one to reach the south meridian then I only need to move the scope to the correct altitude which for me is 37° 37' for this target.

Frank :)

#9 Tom Machtemes

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Posted 27 August 2009 - 09:22 AM

Frank,

:cool:, nice sketch.

:thanx:,

Tom

#10 Jef De Wit

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Posted 27 August 2009 - 01:16 PM

Frank
It's normal that you don't see any green in my sketch. I made it without colouring (just pencil on white paper and inverted).
The green colour was only visible by x92. By x171 (the magnification of the sketch) I didn't noticed any colour. I tried Lumicon UHC, but it didn't make the nebula any better.

#11 CarlosEH

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Posted 27 August 2009 - 09:50 PM

Frank and Jef,

Excellent observations of the Saturn Nebula (NGC 7009). The lobes ("rings") were well rendered in Frank's observation. Thank you both for sharing them with us all.

Carlos

#12 frank5817

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Posted 28 August 2009 - 12:24 AM

Tom, Jef and Carlos,

Thank you much for your comments on my sketch. :thanx:

Jef- I think I may need to make an appointment with an opthamologist.:crazyeyes:

Frank :)

#13 Jeff Young

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Posted 28 August 2009 - 11:23 AM

Nice sketches, guys.

I have four observations logged: one mentions blue, one mentions blue-green, and the other two don't mention color at all.

Go figure. :shrug:

-- Jeff.

#14 rolandlinda3

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Posted 28 August 2009 - 11:38 AM

Very nice and such a pretty object, too. This is an interesting target with color-astrovideo as well but it has been some time since I have looked at it. Nice report.

#15 mickmrn1

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Posted 28 August 2009 - 06:26 PM

Impressive sketch! I like the color and ring detail in this one.

#16 frank5817

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Posted 28 August 2009 - 09:42 PM

Jeff, Roland and Michelle,

Color perception of planetaries seems to vary a little for me. If I observe planetaries after being in the dark for several hours I see the distinctions in color better. Transparency of the sky also seems to play a role.
Thank you for your comments and nice words. :thanx:

Frank :)

#17 Special Ed

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Posted 29 August 2009 - 04:15 PM

Frank,

Nice sketch and an interesting target, too--doubly so if the Great Herschel first saw it. I have never observed it--after the Moon wanes might be a good time while the real Saturn is lost in the glare of the Sun. :)

#18 frank5817

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Posted 29 August 2009 - 09:33 PM

Michael,

Thank you. :thanx:
It is worth a look. With your sky much darker than mine I think you will enjoy the view.

Frank :)






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