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NGC 457 - "Owl Cluster" in Cassiopeia

NGC457 - The Owl Cluster

APM/TMB 130/780
Field Flattener
QSI 583WSG
Astrodon Gen 2 LRGB
L: 12x5min (2x2)
RGB: 6x5min each (2x2)
Imager Temp -10C
50% Crop

The first image from the QSI 583 to have the luminance binned 2x2. My skies are usually marginal enough to be fine for this image scale (2.85 arcsec/pixel) but it still made for pixelated stars in the final image. One benefit was a quicker gathering of data at 5 min subs rather than 10 min subs with clouds rolling in.

NGC 457 - The "Owl Cluster" was discovered by F.W. Herschel in 1787 and is also catalogued as Cr 12, Mel 7, OCL 321, Lund 43, H VII-42, h 97, GC 256. This cluster seems to attract nicknames, and has also been called the Kachina Doll Cluster, the E.T. Cluster, the Owl Cluster and the Nazgul Cluster. The brightest star in the cluster, Phi Cassiopeiae is not a member of the cluster, but a foreground star instead. The cluster is about 9000 light years from the sun.

September 12 and 13, 2010

NGC 457: The "E.T. Cluster" in Cassiopea
LRGB composition of NGC 457: a rich galactic cluster in Cassiopea, also known as E.T. Cluster or Owl Cluster.

Noticeable objects in the field:
* over 100 (probably around 150) stars members of the cluster of magnitude ranging between 12 and 15
* the pair of brightest stars on top of the cluster, Phi-1 and Phi-2, i.e. the eyes of E.T., are not members of the cluster
* several small galaxies overall the field, of which the PGC 4831 near top left, is one of the brightest

Technical data:
RC-14” F/8,4
SBIG STX 16803
LRGB Filters Baader LRGB
Mount: Gemini Telescope Design - MOFOD Fork Mount
L-R:G:B 120-15:15:15 (minutes)
SQM: 21.1
Seeing: 1.6"-1.8"

Authors:
Acquisition: F. Antonucci - M. Angelini - F. Tagliani
Image Processing: Francesco Antonucci

Parco Astronomico del Brallo

NGC 457 ET Cluster

Finally had a couple of clear nights to image. NGC 457 was one of my targets.

Hiçbir yazı/ resim izinsiz olarak kullanılamaz!! Telif hakları uyarınca bu bir suçtur..! Tüm hakları Çetin BAL' a aittir. Kaynak gösterilmek şartıyla siteden alıntı yapılabilir.