NGC 6709 (Lund 866, Cr 392) Open Cluster in Aquila

Located at: RA 18 hours 51 minutes 30 seconds, Dec +10 degrees 20 minutes 00 seconds

Size: 13' (15') Magnitude: 6.7 Class: IV 2 m

North is up

West to the right

Telescope:

8" f5 Newtonian reflector

Camera:

 ST-8XME, self-guided, binned 1x1, temp -20c, camera control MaxIm DL 4.56

Image:

Lumicon Deep Sky filter, 150 minutes (15 x 10 minute subs), 09/16/2007

Processing:

CCDStack 1.3, Photoshop 7.0

Location:

 Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s)

Notes: According to "Star Clusters", by Brent Archinal and Steven Hynes, the size of this open cluster is 15 arc minutes.

From the NGC / IC Project:

Contemporary Visual Observation(s) for NGC 6709

NGC 6709 = Cr 392 = Mel 214 = Lund 866
18 51 18 +10 19.1
V = 6.7;  Size 13

18" (8/14/04): excellent open cluster at 115x with roughly 100 stars mag 10-13.  
Appears triangular, ~20' diameter with an additional loop of stars bowed out to 
the south attached at the ends of the southern side of the triangle.  At the 
eastern end is a distinctive 22" pair of mag 9/9.5 stars oriented SSW-NNE, with 
the SW star an orange color.  A closer 10" pair 1' E forms a quadrilateral with 
this brighter pair. The stars are irregularly distributed with some vacant 
regions and there appears to be dust throughout the field, particularly west of 
the cluster but also intruding into the cluster.  A N-S string of a half-dozen 
stars is on the west side forming one of the bases of the triangle.

17.5": over 100 stars mag 9-14 resolved in a 15-20' field but not dense.  
Appears best at 83x-105x.  An easy mag 10 double star at 22" separation is at 
the east side and a close fainter pair follows.

13": fairly large, about 70 stars in cluster, includes some close double stars.

- by Steve Gottlieb
Historical Research Notes / Correction for NGC 6709
NGC 6709 may also be NGC 6724, which see. - Dr. Harold G. Corwin, Jr.
Historical Research Notes / Correction for NGC 6724
NGC 6709 may also be NGC 6724, which see. - Dr. Harold G. Corwin, Jr.
=================================================================
NGC 6724 is described by JH simply as "A cluster discovered with the 7-feet
(sic) equatorial, Sept 5, 1828."  He puts a plus/minus sign on the RA which 
he lists to only a full minute of time, though the Dec is given to his usual
precision of an arcsec.

About five arcmin northwest of his place is a small (5 arcmin by 3 arcmin)
clump of stars, a dozen of which are bright enough to be in GSC.  Given the
paucity of information, though, the object could also be NGC 6709, a much
richer cluster 10 minutes west at the same declination.  Until further data
can be dug out of JH's original observing notes (assuming there is more data),
I am going to adopt the poorer clump of stars for this number -- though with
a colon to flag the uncertainty inherent in the observation.
 - Dr. Harold G. Corwin, Jr.