NGC 4755 – JEWEL BOX OPEN CLUSTER

Crux

 (ra: 12:53,6 / dec -60:20)

June 2009, Home Backyard in Martínez, Buenos Aires, Argentina

DATA

TYPE: Open Cluster

VISUAL MAGNITUDE: 4.2

SIZE: 10 arc minutes

DISTANCE: 7600 light years

OBJECT DESCRIPTION

This open cluster is a beauty of the Southern Sky. It is one of the youngest clusters known carrying 7.1 Millions of years of existence. The three brightest stars are blue giants and shine at magnitudes 5.75, 5.974 and 6.8 respectively. The fourth is a red super giant and shines at magnitude 7.58. It can be observed with binoculars and is an easy target to find. Pointing south (pole) its a approximately one degree from Beta Crucis.

It was discovered by Abbe Lacaille during a trip to South Africa in 1751-1752.

IMAGE INFORMATION

SCOPE: Celestron C8 SCT working at f6 (roughly)

CAMERA: SXVF H9

GUIDING: William Optics Zenithstar 66 with WO 0.8 x fr/ff

IMAGE ACQUISITION: AstroArt 3.0 - Control Interface 3.72 plug in

FILTERS: Astronomik Type II - Astronomik Ha 6 nm - Atik Filter Wheel

SKY CONDITIONS: rural skies - transparency and seeing regular

EXPOSURES: LRGB (40,10,10,10)

PROCESSING: Calibrated in Images Plus, Adaptive Add, (no darks, no flats, no bias) CCD Sharp, Photoshop CS2