NGC 4755

 OPEN CLUSTER IN CRUX (AKA THE JEWEL BOX)    

(Image centered at: ra 12 h:55 m / dec - 60º 29')

May 2023, Home Backyard in Martinez, Buenos Aires, Argentina

DATA

TYPE: Open Custer

APPARENT DIAMETER: 10 arc minutes

APPARENT MAGNITUDE (V): 4.2

DISTANCE: 6400 light years

IMAGE INFORMATION

INSTRUMENT: 6" ORION OPTICS UK (Ultra Grade Optics) w/Sky Watcher Coma Corrector (0.9x) working at at f4.5

CAMERA: QHY 183 MONO

MOUNT: SKY WATCHER NEQ6, OAG with Starlight Xpress Lodestar

FILTERS: Optolong LRGB Set

SKY CONDITIONS: urban skies - Bortle 8

EXPOSURES: LRGB 30,30,30,30)

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OBJECT DESCRIPTION AND IMAGE SESSION

The Jewel Box (also known as the Kappa Crucis Cluster, NGC 4755, or Caldwell 94) is an open cluster in the constellation Crux, originally discovered by French astronomer Nicolas Louis de Lacaille in 1751–1752. This cluster was later named the Jewel Box by John Herschel when he described its telescopic appearance as "...a superb piece of fancy jewellery". It is easily visible to the naked eye as a hazy star some 1.0° southeast of the first-magnitude star Mimosa (Beta Crucis). This hazy star was given the Bayer star designation "Kappa Crucis", from which the cluster takes one of its common names. The modern designation Kappa Crucis has been assigned to one of the stars in the base of the A-shaped asterism of the cluster

This cluster is one of the youngest known, with an estimated age of 14 million years. It has a total integrated magnitude of 4.2, is located 1.95 kpc. or 6,440 light years from Earth, and contains just over 100 stars.

This image was processed with Russell Croman Photoshop Plug Ins.