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The Great Barred Spiral Galaxy ( NGC 1365 ) in the constellation Fornax

edit: new version with new long exposure data ( 52 x 240sec ) and better dark subtraction / dithering to remove streaks in the noise and amp glow.  This also allowed for a greater stretch revealing more faint data in the galaxy and small faint fuzzies in the image ..

EA2D66A5-4277-4782-9C99-715EAC778B06.thumb.jpeg.688cf82f28393e8e916428be423f8b40.jpeg

The Great Barred Spiral Galaxy ( NGC 1365 ) in Fornax ( please click / tap to see larger )

and below I have added a 100% crop of new version:

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original image:

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NGC 1365  ( please click / tap on image to see larger )

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The Great Barred Spiral Galaxy (  NGC 1365 ) in the Constellation Fornax

Below the equator, not seen from much of the Northern hemisphere, NGC 1365 passes very nearly directly overhead an observer situated near Cape Town, as Sir John Herschel was in November of 1837, or near Sydney, as I was, almost exactly 180 years later, when I photographed this “remarkable nebula” that is numbered 2552 in his book of observations from the Cape.

Not called a “nebula” now, of course, this striking object is one of the nearest and most studied examples of a barred spiral ( SB ) galaxy that also has an active galactic nuclei resulting in its designation as a Seyfert galaxy.

At around 60 M light years from Earth, NGC 1365 is still seen to occupy a relatively large area ( 12 by 6 arc minutes ) due to its great size; at some 200,000 light years or so across, NGC 1365 is nearly twice as wide as the Milky Way and considerably wider than both the Sculptor and Andromeda galaxies.

This High Dynamic Range ( HDR ) image is built up from multiple exposures ranging from 4 to 120 seconds with the aim of capturing the faint detail in the spiral arms of the galaxy whilst also retaining colour in the brightest star ( the orange-red 7th magnitude giant, HD 22425 ).  Also, scattered throughout the image, and somewhat more difficult to see, are numerous and far more distant galaxies with apparent magnitudes of 16 to 18 or greater.

Mike O'Day

 

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Identification:

The Great Barred Spiral Galaxy
New General Catalogue -  NGC 1365
General Catalogue -  GC 731
John Herschel ( Cape of Good Hope ) # 2552 - Nov 28, 29 1837
Principal Galaxy Catlogue - PCG 13179
ESO 358-17
IRAS 03317-3618

RA (2000.0) 3h 33m 37.2 s
DEC (2000.0) -36 deg 8' 36.5"

10th magnitude Seyfert-type galaxy in the Fornaux cluster of galaxies
200 Kly diameter
60 Mly distance

 

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Capture Details:

Telescope: Orion Optics CT12 Newtonian ( mirror 300mm, fl 1200mm, f4 ).
Corrector: ASA 2" Coma Corrector Quattro 1.175x.
Effective Focal Length / Aperture : 1400mm f4.7

Mount: Skywatcher EQ
Guiding: TSOAG9 Off-Axis-Guider, Starlight Xpress Lodestar X2, PHD2 

Camera:  Nikon D7500 (unmodified) (sensor 23.5 x 15.7mm, 5568x3712 @ 4.196um pixels)

Location:
Blue Mountains, Australia 
Moderate light pollution ( pale green zone on darksitefinder.com map )

Capture ( 22 Nov 2017 )
6 sets of sub-images with exposure duration for each set doubling ( 4s to 120s ) all at ISO400.
70 x 120s + 5 each @ 4s to 60s
total around 2.5hrs 

 

Processing ( Pixinsight )
Calibration: master bias, master flat and no darks
Integration in 6 sets
HDR combination 

Image - Plate Solution
==========================================
Resolution ........ 1.328 arcsec/px
Rotation .......... -0.008 deg  ( North is up )
Field of view ..... 58' 8.6" x 38' 47.5"
Image center ...... RA: 03 33 41.182  Dec: -36 07 46.71
==========================================

Edited by MikeODay
Updated 100% crop added
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Thanks Alan.

Mmm, the skies are not too bad where I am I guess but I am still in the pale green zone; I would love to live somewhere with truly dark skies :)

And yes, very high up for me - almost to the zenith.

Cheers

Mike

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That is such a stunning capture wit a 12" Newton! Congratulations. I first thought it was the same galaxy as the one I had processed from Liverpool Telescope data (a 2 m RC scope) a few months ago, but not, and yours looks even better. So here is the Northern hemisphere twin, the NGC 1530 (I expect it to be further away since the resolution is less with the 2m scope, or you must have a super charger on your Newton)

NGC1530 RGB image from Liverpool Telescope data

 

Edited by gorann
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16 hours ago, Saganite said:

A glorious Galaxy and a stunning image !

I did manage some binocular observing, a few years back when I visited my Daughter, in Katoomba.

 

Cheers Steve.

How did you find using binoculars in the mountains?  I was wondering whether it might be an idea to set up a pair to look through while my rig churns away on taking images ( I tried holding them by hand but the shake was too annoying :) ). 

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7 hours ago, gorann said:

That is such a stunning capture wit a 12" Newton! Congratulations. I first thought it was the same galaxy as the one I had processed from Liverpool Telescope data (a 2 m RC scope) a few months ago, but not, and yours looks even better. So here is the Northern hemisphere twin, the NGC 1530 (I expect it to be further away since the resolution is less with the 2m scope, or you must have a super charger on your Newton)

 

 

Thanks Goran, much appreciated.

That is a fantastic image of what is really quite a tiny object; in my scope NGC 1530 would be just a little blob in the middle!

Cheers

Mike 

 

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B84727C5-3A51-4D26-A71B-0389C261229D.thumb.jpeg.9a25ea9d6cf023ba4247d5152645c499.jpeg

CF2D4CEA-B4EA-4A63-8272-0D5EA593185E.thumb.jpeg.40908f09c406fb85736895b22465ea3a.jpeg

The Great Barred Spiral Galaxy ( NGC 1365 ) in the constellation Fornax

( Quick tweak on my Ipad ( contrast increase and slight sharpening ) to darken noise on brighter screens and bring out more of the detail in the arms of the galaxy. )

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Mike, thanks a stunning target, and a stunning image of it - you've really captured the outer arms. You constantly amaze me at what you can achieve with a DSLR.

I love barred galaxies - sadly I can't reach this one and I don't have a 2-meter scope yet for it's northern twin - (but who knows - maybe Santa will bring me one!).

Edited by Petergoodhew
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22 hours ago, Petergoodhew said:

Mike, thanks a stunning target, and a stunning image of it - you've really captured the outer arms. You constantly amaze me at what you can achieve with a DSLR.

I love barred galaxies - sadly I can't reach this one and I don't have a 2-meter scope yet for it's northern twin - (but who knows - maybe Santa will bring me one!).

Thanks Peter, that is very kind of you.

I assume that Santa must be feeling generous and in happy mood as he visits the homes nearer to the North pole - by the time he gets down here I am sure he is feeling pretty grumpy and just throws out the left-overs :)

 

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18 hours ago, Rodd said:

One of the best images of a galaxy I have seen--perfect.  Amazing.  That focal length and focal ratio is a great combination

Rodd

Thank you Rodd, much appreciated.  I am really pleased with the scope and with my new Feather Touch focuser and D7500 camera.

Having said that, this was the ‘first light’ with my new Nikon D7500 and I still have a bit of experimenting to do in order to find the optimal exposure settings and processing.  The thermal noise does appear to have a very low level fixed pattern that I may have to try to deal with.  In this case I messed up dithering and produced a near constant rate of drift in one direction and hence the stripes in the low level noise.  Correct dithering may fix most of the pattern noise but there is also very low level amp glow at the left that I don’t think dithering will fix.  

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3 hours ago, MikeODay said:

hence the stripes in the low level noise.

Now that you mention this I took a closer look at the background and see what you mean.  Its always something.  Your processing skills have almost eliminated the pattern.  

Rodd

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