Object of the Week June 24, 2012 – NGC 5907 "The Splinter Galaxy"

[Dragan]

NGC 5907 - The Splinter Galaxy

Galaxy

Draco the Dragon
RA 15 15 53.9
DEC +56 19 38

Mag 10.3
Size 12.9'x 1.3'

Within the body of the Dragon and located approximately 1.4 Degrees to the NW of M102 lies NGC 5907, The Splinter Galaxy. 5907 is a moderately bright edge-on spiral with a definitive dust lane visible with modest aperture. This object has been faintly observed with scopes as small as a 4" but it'll take larger glass and dark skies to see the dustlane.

I've observed this galaxy many times with my 25" and the dustlane can be very pronounced. The galaxy shows well at 315x as the dustlane can be quite contrasty against the brighter galaxy and knots can start to be seen. Under moments of good seeing you can make out quite a bit of detail in dustlane. A great overall object to observe and worthy of an OOTW title!

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With this object I do bring a couple challenges...

1. What is the smallest aperture the galaxy can be observed with? How about the dust lane?

2. This is more suitable for the AINTNO list and only reserved for the largest of mirrors and darkest of skies, but has any component of NGC 5907's tidal streamers been visually observed?

Tidal streamers that are associated with 5907 have been photographed and probably arise from a past cosmic collision. These streamers are faint!! The streamers have been captured in deep images but I don't believe I've ever read about anyone picking any of it up with their eyes. (not that I really have expected too ;))

Here is a link to a website with more information and a great photograph. NGC 5907 Tidal page (http://www.cosmotography.com/images/small_ring_ngc5907.html)

So there you go... an impossible challenge! :P But with that being said, there have been many, many amazing feats accomplished by many experienced observers, so maybe this isn't as crazy as it first sounds.... we won't know until we try, right?

Thanks for reading this weeks OOTW. Remember folks, if you have an object you'd like to post as your own, please do not hesitate to contact us about getting in the queue!

But most importantly.....

"GIVE IT A GO AND LET US KNOW"

GOOD LUCK AND GREAT VIEWING!

[Jeff Young]

I could "see" the dark lane several years ago with a 16" mirror at 170X. From my notes:

"More elongated than NGC891, with a more condensed core, but dark lane not as prominent. In fact, it would be fair to say that the dark lane is only hinted at, perhaps more so at lower magnification (110X), but still fleeting. It is enough to detect offset to W of center. Extent about 7' in direct, extending to 12' in averted. Nice question-mark asterism to N."

Conditions on the night were fairly poor (Pickering 4, NELM 5, SQM 20.2).

Cheers,
Jeff

[Marko]

This is one of those objects that is in the range of a Messier Class object with a handful of others that missed the list from our northern skies. Always a treat and stands in the league of Ngc4565 but with no pronounced central bulge and a less obvious dark lane. A curious common trait is the location of a field star just off of the center of both although that is not really a trait of either of the actual galaxies.

To me this galaxy was quite a shock to run across the first time and is a real treat. Here is an observation from 2010 from an 18" in dark skies of about SQM 21.5/Nelm 6.5 range.

2/3fov [12'] 11EL 150dPA Pencil thin, huge and very thin. Bright central core area about 2' in len along major axis. Leading FStar perpendicular out to the West from the center of core (like 4565 FStar)

I did not note the dark lane and think I would have mentioned it if I had seen it. For sure I will re-visit this next new moon at GSSP as this is a favorite eye-candy object.

Thanks for the timely reminder Dragan!
Marko

[RolandosCY]

We observed this galaxy last night, from a green zone (near the border with yellow). With my 18" I could detect easily the dark lane, and I was impressed by the the large size of this galaxy. I made a detailed sketch but have yet to scan it. No sight of the streamers though.

We failed to detect the galaxy on my friend's (NicosCY) 4" Stellarvue that was set next to my 18". I have to admit I did not really spent much time looking for it through the Stellarvue, but Nicos also failed to see it (though nearby NGC 5866 was readily visible). I do believe that with a little bit of more effort we might had detected it in the refractor. It should be readily detectable from a high altitude / darker site.

[RolandosCY]

Well, as I mentioned earlier, I made a detailed sketch of NGC 5907 which I finally digitized today. I must admit I was amazed myself at how much detail there is in this galaxy. OK, the obvious feature was the dark lane, which certainly did not have straight edges and which did not extend throughout the long axis of the galaxy. Also, the width of the lane was considerable and could account for the rather low surface brightness of the whole galaxy.

In addition, there was an elongated brighter core near the center of the NE side of the galaxy which to my eye appeared rather turbulent with no distinct nucleus. All in all a very ompressive galaxy! Thanks to Dragan for the heads up!

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[nicoscy]

Seeing conditions were definitely not optimal, with fluctuating humidity levels wreaking havoc on lenses/ mirrors/ finderscopes e.t.c, but I did manage at around 22:30 last night to identify the target.

Due to the rapidly changing conditions, NGC 5907 kept blinking on and off, requiring constant switching to averted vision to maintain sight of the galaxy.

The increased altitude (4,500 + feet this time) vs our last attempt with Rolandos CY and the use of a TV Ethos 6mm yielding a magnification of 108x was enough to do the trick, as confirmed by Rolandos as well.

This DSO goes in the list of objects to revisit, as I am confident that under better conditions I will be able to squeeze out more detail. As matters stand, I am happy with the detail present in a 4" refractor.