NGC 6781 and HCG 99

NGC 6781
NGC 6781

A brief window to observe the deeper sky was taken tonight as it was clear, dark early and with the moon not due to interfere until around 20.30ut.
As has become the norm, I was intent to grab another of the 100 Hickson groups, but before I did this and as Altair (Alpha Aquilae) was a stop off on my hopping progress up into Pegasus I took a look into Mark Bratton’s excellent Guide to the Herschel Objects to see what was local. I picked up on NGC 6781 which is a beautiful mag 11.8 planetary in Aquila with plenty of exquisite detail to enjoy. Compared to M57 the Ring Nebula in Lyra it is relatively large and faint, yet not so faint that it isn’t visible in smaller, say 8” telescopes, I feel it is more akin to the Helix nebula, though considerably smaller at 2.0′ diameter.
At 16.8 magnitude, the central star (a white dwarf) is clearly seen just off centre in my sketch, made using the 500mm mirror, Watec 120N+ video camera of course! Sketched in pencil on white and then inverted on the computer.
No time to spare, one sketch in the bag, yeeha!, with the Moon getting ever closer to the horizon, I pushed onto Hickson 99 there are 5 members in this group which is located just SW of Alpha Andromedae (Alpheratz) in the square of Pegasus.
(A) member UGC12897 mag 14.8 is extended N-S with a star on its southern tip. (B) UGC12899 is round fairly bright at mag 14.7 with a brighter nucleus. I find (C) PGC 58 to be the most interesting, it is a barred spiral and despite being only mag 15.6 I was able to see and capture arm structure in my sketch, amazing J (D) & (E) members PGC 60 & PGC 57 respectively at mag 17.1 & 17.6 are merely tiny smudges to the south of the 3 main members.
I was very pleased with this short and productive observing session, time to close up and return to the family & gardeners world indoors!

HGC 99
HGC 99

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2 thoughts on “NGC 6781 and HCG 99”

  1. Dale,

    I knew I forgot to do something important this morning – come over to ASOD to see what’s up.

    Two beautiful deep sky treasures by one of my favorite sketchers. Well done.

    Clear skies to you.
    Frank 🙂

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