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NGC 231 (442 of 18,816)

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NGC 231

NGC 231, Cl Kron 20, Cl Lindsay 25, ESO 29-5, OGLE-CL SMC 11, h 2340, GC 123

RA: 00h 41m 6.16s
Dec: −73° 21′ 7.1″

Con: Tucana
Ch: MSA:502, U2:460, SA:24

Ref: SIMBAD

(reference key)

Type: open cluster

Mag: B=13.14, V=12.87

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 "an irregular train of stars and nebulosity in the Nubecula Minor." He notes that it may be equivalent to Dunlop 2.

West to east there are NGC 220, NGC 222, and NGC 231.

Dunlop, James (1828)

Dunlop, J. (1828) A Catalogue of Nebulae and Clusters of Stars in the Southern Hemisphere, Observed at Paramatta in New South Wales. Phil. Trans. Roy. Soc., 118, 113-151. [1828RSPT..118..113D]

Dunlop 2 was discovered by James Dunlop from Paramatta, New South Wales, and included in his catalogue of 1827. Using a 9-inch f/12 telescope, he described it as "a faint nebula, about 1.5' long, irregular figure, rather branched. This is involved in the margin of the Nebula minor."

Published comments

Kron (1956)

Kron, G. E. (1956) Star Clusters in the Small Magellanic Cloud: I. Identification of 69 Clusters. PASP, Vol. 68. [1956PASP...68..125K]

Describes it as a blue cluster, noting the presence of bright blue giant stars. He notes that it is concentrated towards the centre, has a star nearby and exhibits emission nebulosity. Lindsay ("Clusters in the Small Magellanic Cloud", Irish Astronomical Journal, Vol. 4, 1956) classifies it as an open cluster.

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a 12.0 mag open cluster in the SMC.

Modern observations

Brian Skiff

15cm - lgr dispersed cl w/o concen NE of N220/22 pair. 2' diam w/15 *s m14+

@ 140x. BS, 9Nov1993, LCO.

Contemporary observations

Auke Slotegraaf

1997 October 09

11x80: 1997-10-09, 02:30, Jonkershoek, seeing 3, transparency 3, darkness 3 "Not found."

Favourite lists

Lacaille's catalogue

The Messier objects

Dunlop's catalogue

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The Caldwell list

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