Object of the Week, July 19th, 2015 - Open cluster = Asterism?, NGC 6802, in Vulpecula

[Paul Alsing]

Object of the Week, July 19th, 2015 - Open cluster = Asterism?, NGC 6802, in Vulpecula
NGC 6802
R.A.: 19h30m35.0s
Dec.: +20°15'42" (2000)
Size: 5.0'
Mag: 11.70

My apologies for the lateness of this report, I was at a star-party all of last week and didn't return home until very early Monday morning... and then, of course, forgot all about it until today :>(

This OOTW is not glamorous, difficult, or particularly special, but it is a bit unusual. It is located in Vulpecula, directly off the eastern edge of Collinder 399, the famous Coathanger asterism, and is therefore pretty easy to find. It is small and rich, but dimmed by all the dust in the area. It is elongated north to south, and I consider it to be a dainty little cluster.

I spend a lot of time creating my 'library' documents (link in my signature). I do this instead of writing random notes about various objects that I have read about on amastro (https://groups.yahoo.com/neo/groups/amastro/info) or on other observing discussion web pages, because keeping track of hundreds and hundreds of notes concerning hundreds and hundreds of potential targets can get out of hand rather quickly. My library is essentially my roadmap. Anyhow, a few years ago there was this thread concerning NGC 6802, and 3 guys were going back-and-forth about this little guy, having observed together previously, and all of them agreed that this cluster should be dubbed as "The DNA Strand". It is a very funny exchange, and I urge to read it... http://tinyurl.com/okhzzjd


NGC 6802.jpg

I agree with Greg, Dana and Marko in that no photo I can find of NGC 6802 looks anything like a DNA strand, but in the eyepiece I couldn't agree more... it really does!

As always, give it a go and let us know!

[Mark McCarthy]

Paul,

I saw this odd shape too: 9/27/14, Lake San Antonio, CA (CalSTAR): 12.5" f/7, 170x, 5.5 NELM: "Faint! Clot of stars, two loops forming a figure 8. Fine grainy stars behind. Need AV to see it clearly. Off last Coathanger star to West" This was early in the evening so I believe it would have shown up better in a properly dark sky.

And please let me take the opportunity to thank you for your website, which is a treasure trove I'm sure to use for a long time.

[wvreeven]

Using my 20" I didn't notice a DNA-like or figure 8 like shape, but noted it down as oval, nearly rectangular. Using my 6" I saw it as a faint smudge with a few stars in it, especially at high (i.e. ~200x) magnification.


Clear skies,

Wouter

[Howard B]

I didn't notice the DNA shape - which sounds really cool - in my only recorded observation of 6802, which is from 1993 with my 20 inch Obsession:

"Nice little open cluster next to the Coathanger - lots of faint stars, elongated north-south. No bright stars near the center. 182x"

I did see an elongation of the cluster, so perhaps I merely suffered from a failure of imagination or attention to not see the DNA shape - all the more reason for another look.

[Ivan Maly]

It is a favorite since the time I viewed it with my 4" Petzval. From last year come these notes (16", rural site):

NGC 6802, class VI, is the cluster at the end of the Coathanger. It is obvious at the low power [45x], unresolved save for perhaps 1 or 2 members in the center. Appears textured, elongated 3x1 NS. At the high power [225x], the ends no longer appear tapered. The E side looks flattened and the W one jagged. The cluster seems to be fully resolved, although many stars are just on the threshold. Brighter stars are on the N end. Overall the stars are relatively uniform.

[Uwe Glahn]

Very nice OC Paul. I often took the cluster to test the transparency with small aperture. And I did not notice any DNA structure but will revisit the object and look at that.

4", 17x, NELM 6m+
Cr399.jpg