NGC 4755 (Jewel Box Cluster) in Crux

(move the mouse over thumbnails - please be patient until image downloads)

    12" ASA: LRGB 12" ASA: LRGB - 150% crop    
    Size: 2000 px Size: 2000 px    
Downloading, please wait ...
© Velimir Popov & Emil Ivanov 2013

NGC 4755 (also known as the Jewel Box, Caldwell 94 or Kappa Crucis Cluster) is an open cluster in the constellation Crux. It was discovered by Nicolas Louis de Lacaille in 1752. Later this cluster was named "the Jewel Box" by Sir John Herschel, who described its telescopic appearance as "a casket of variously coloured precious stones." It can be easily found by the naked eye as a hazy star some 1.0° southeast of the star Beta Crucis (Mimosa). Its other name (Kappa Crucis) was given by its original Bayer star designation. Since known as a star cluster, the second brightest cluster star, placed within the main A-shape, became known as Kappa Crucis. This is one of the youngest known star clusters, with an estimated age of 14 million years. Its total integrated magnitude is 4.2, and it is located 6,440 light years from Earth.

Object details

Right Ascension 12:53:42 (h:m:s)
Declination -60:22:00 (deg:m:s)
Size -
Distance 6.4 (kl.y.)

Image details


Center of field RA 12:53:29 (h:m:s)
Center of field DE -60:19:00 (deg:m:s)
Size 57 x 42.9 (arcmin)
Pixel scale: 1.03 (arcsec/pixel)
Orientation: Up is 177 degrees E of N
Charts and image details obtained from
Optic(s): ASA 12" f 3,6 Astrograph (ASA)
Mount: ASA DDM85
Camera: FLI MicroLine 8300 CCD camera
Filters: Red, Green, Blue, Astrodon
Dates/Times: 3 May 2013
Location: Namibia-TIVOLI ASTROFARM, S 23° 27' 40,9" / E 18° 01' 02,2"
Exp. Details: R:5x5min, G4x5min, B:4x5min, Total Exposure Time - 65 min
More details: Dark and flat frames reduction
Processing: PixInsight / PS
Copyright: Velimir Popov and Emil Ivanov 2013. All Rights Reserved
click tracking