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NGC 5120 (11,433 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 5120

NGC 5120, Cl Ruprecht 166, ESO 96-11, Ocl 899, C 1322-631, h 3496, GC 3518

RA: 13h 25m 39s
Dec: −63° 27′ 30″

Con: Centaurus
Ch: MSA:1000, U2:451, SA:25

Ref: SIMBAD, DAML02, Archinal&Hynes (2003)

(reference key)

Type: open cluster, 21m

Mag: B=11.68, V=10.8

Size: ?
PA: ?

Historical observations

John Herschel (1847) Cape Observations

Discovered by Sir John Herschel at the Cape of Good Hope with an 18-inch f/13 speculum telescope. He recorded it as "cluster class VI; oval; 4' long, 3' broad; stars 12..16th mag; an extremely rich clustering patch in the milky way, which is here superb."

Published comments

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a nonexistent object. Their coded description reads NOCL) S.

Vogt. N. & Moffat, AFJ (1973)

Vogt. N. & Moffat, AFJ (1973), "Southern Open Star Clusters III." Astron.Astrophys.Suppl., 10, 135-193. [image, table]

Ruprecht 166

"Only three stars in the cluster area have been measured. None of these is of early type and presumably they belong to the general field. If the cluster exists its brightest star is most likely fainter than V = 13m. However, its existence is doubtful in view of the relatively high field star density in the vicinty of the supposed cluster region.

Piatti & Clariá (2001)

Ruprecht 166

Piatti, A. E. & Clariá, J. J. (2001) On the nature of five open cluster candidates projected close to the Galactic centre. Astronomy and Astrophysics, 379, 453-460. [2001A&A...379..453P]

Abstract: We present CCD BVI observations obtained for 1759 stars in 4arcmin x4arcmin regions around the unstudied southern stellar aggregates Ruprecht 103, 124, 129, 146 and 166, which are described as open clusters in several catalogues. Our analysis shows that none of these stellar groups are genuine open clusters since no clear main sequences or other meaningful features can be seen in their colour-magnitude diagrams. Star counts carried out within and outside the cluster candidate fields not only support these results but also show that the studied objects do not appear to be candidate late stages of star cluster dynamical evolution. Based on observations made at the University of Toronto (David Dunlap Observatory) 24-inch telescope, Las Campanas, Chile. Tables 2 to 6 are only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr ( or via http://cdsweb.u-strasbg.fr/cgi-bin/qcat?J/A+A/379/453

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