Astrophotography by Anthony Ayiomamitis

Deep Sky Object Image Gallery

Open star clusters are widely distributed in our galaxy and represent a loose collection of stars which number from a few dozen to a few hundred stars and are weakly-held gravitationally. Perhaps the three most famous such open clusters are the Pleiades (M45) in Taurus, the Beehive (M44) in Cancer and the double cluster in Perseus. They are all characterized with a handful of hot and white prominent stars and nebular material surrounding these stars.

Note: Open cluster NGC 6940 in Vulpecula has been estimated to be approximatelty 700 million years-old, thus making this bright and rich open cluster with over 100 member stars of intermediate age. The cluster lies approximately 2,500 light-years away and near the border border between Vulpecula and Cygnus. As indicated by the image below, the cluster is well detached from the background sky and without a central concentration with the reddish star HIP 101527 (FG Vul, mag 9.13) marking its approximate center (also note the impressive double star to the southwest with a separation of 4.5 arc-seconds). NGC 6940 was discovered by William Herschel in 1784.

Please click on the image below to display in higher resolution (1200 x 900)

Image Details
NGC 6940 - Open Cluster in Vulpecula
Imaging Details
NGC Number:
6940

Common Name(s):
N/A

Other Designations:
Mel 232, OCL 141

Object Type:
Open Cluster

Object Classif:
III 2 r

Constellation:
Vulpecula

RA / Dec:
20h 34m 16s /
28 17' 00"


Distance:
2,510 light-yrs

Object Size:
25'

Magnitude:
6.3
Date:
Sep 4, 2008
21:50 - 00:00 UT+3


Location:
Athens, Greece

Equipment:
AP 160 f/7.5 StarFire EDF
AP 1200GTO GEM
SBIG ST-2000XM
SBIG CFW10
SBIG LRGB + IR-block


Integrations:
Lum :  030 min (10 x 3 min)
Red :  030 min (05 x 6 min)
Green :  030 min (05 x 6 min)
Blue :  030 min (05 x 6 min)
Dark :  135 min (15 x 3+6 min)
Flat :  ~ 18,000 ADU
Binning :  1x1 (Lum),  1x1 (RGB)

Temperatures:
Ambient : + 22.0 C
CCD Chip : - 10.0 C

Software:
CCDSoft V5.00.188
CCDStack V1.3.7
Photoshop CS2