Observation Notes:
This is the first deep sky observation I've made from my home in a long time. I feel a debt to my observations and sketches to give deep sky objects the darkest sky I can find. But I'm finding fewer and fewer opportunities to pack up and drive to a dark site to observe these days (as if you hadn't already noticed ;). So I bought some materials (PVC pipe, connectors, tarps and bungie cords) to assemble a temporary light shield in my front yard so I can get back to observing non-challenge DSOs from home again. With the glaring industrial lights blocked, I examined the star field around M57 and was able to get down to magnitude 14.1. Not bad I guess--that's Pluto territory. Anyway, this is where NGC 6910 comes in. It's my first sketched observation using the new light shield set up.
At low power, this open cluster makes a beautiful pair with Sadr's brilliant orange light. A magnification of 120X however, shows off more stars within the cluster itself. The body of this stellar family is guarded by two bright stars--a yellow beacon to the southeast and an orange-yellow sentinel to the northwest. I estimate the diameter of the cluster to be about 5.5 arc minutes. I plotted 23 stars within the general boundaries of the cluster, adding to a total of 68 stars in the overall view.
I thought I was picking up a glow across the arc of the cluster's core, especially around the bright southeast star. I don't know if that glow came from unresolved stars, or if I was experiencing reflections in the eyepiece. I tried the ultrablock filter to see if the emission nebula was showing up, and the glow still seemed to be there, but I still can't be sure if it was my cheap 10 mm Plössl playing games with me. I really need a better 10 mm EP.
Object Information:
NGC 6910 was discovered by F.W. Herschel in 1786. It is also catalogued as Cr 420, Lund 950, OCL 181, H VIII-56, h 2077, GC 4575.
Subject | NGC 6910 |
Classification | Open Cluster (I 3 m n) |
Position | Cygnus [RA: 20:23:12 / Dec: +40:46:43]* |
Size* | 7' |
Brightness* | 7.4 vMag |
Date/Time | August 12, 2007 - 01:00 AM MST (August 12, 2007 - 08:00 UT) |
Observing Loc. | Flagstaff, AZ - Home |
Instrument | Orion SVP 6LT Reflector (150 mm dia./1200 mm F/L) |
Eyepieces/Mag. | 10 mm Sirius Plössl (120X) |
Conditions | Mostly clear, calm, some passing high clouds |
Seeing | 4/10 Pickering |
Transparency | ~ Mag 5.8 NELM |