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: The open cluster NGC 7654 depicted below lies between -Cas and -Cep covering an area approximately 16'x16' and with an apparent diameter of about 20 light-years across. The cluster also lies 35' from the well-known Bubble Nebula (H-II emission nebula) and is generally in a rich portion of the sky due to the surrounding Milky Way. Distance estimates for this 35 million year-old cluster vary dramatically and range from 3,000 to 7,000 light-years with a number of estimates centered around 5,000 light-years. As indicated by the image below, NGC 7654 is quite rich with an estimated 190 member stars which are dominated by two yellow giants (mag 7.8 and 8.2) as well as the main sequence star SAO 20597 (mag 9.0). The cluster was first observed by Charles Messier in September, 1764 and which he entered in his famous catalog as the fifty-second entry (M52). This circumpolar open cluster lies at the midpoint between Cepheus and Cassiopeia (as noted above) and is best observed during fall and winter when it is due north of the celestial pole in late evening.

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

Image Details
M52 - Open Cluster in Cassiopeia
Imaging Details
NGC Number:
7654

Common Name(s):
M52

Other Designations:
Cr 455, Mel 243

Object Type:
Open Cluster

Object Classif:
II 2 r

Constellation:
Cassiopeia

RA / Dec:
23h 24m 50s /
61 36' 24"


Distance:
5,000 light-yrs

Object Size:
16' x 16'

Magnitude:
7.3
Date:
Nov 27, 2011
18:45 - 21:20 UT+3


Location:
Athens, Greece

Equipment:
AP 305/f3.8 Riccardi-Honders
AP 1200GTO GEM
SBIG ST-10XME
SBIG CFW10
SBIG LRGB filters


Integrations:
Lum :  030 min (30 x 1 min)
Red :  030 min (10 x 3 min)
Green :  030 min (10 x 3 min)
Blue :  030 min (10 x 3 min)
Binning :  1x1 (L),  1x1 (RGB)

Image Scale:
1.25" per pixel

Temperatures:
Ambient : + 08.0 C
CCD Chip : - 25.0 C

Software:
CCDSoft V5.00.201
CCDStack V1.6.0.5
eXcalibrator V1.0.3.0
Aladin V6
Photoshop CS2