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NGC 6603 (15,080 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 6603

NGC 6603, Cl Collinder 374, Cl Melotte 197, ESO 590-17, Bennett 107A (in Messier 24), h 2004, GC 4397

RA: 18h 18m 26.9s
Dec: −18° 24′ 22″

Con: Sagittarius
Ch: MSA:1368, U2:339, SA:15

Ref: NGC/IC, Archinal&Hynes (2003)

(reference key)

Type: open cluster, 12r

Mag: B=?, V=11.1

Size: 5′
PA: ?

History and Accurate Positions for the NGC/IC Objects (Corwin 2004)

NGC 6603, a relatively small and faint cluster, is not M24. The Messier object is actually IC 4715, which see for more.

Published comments

Melotte, P.J. (1915)

A catalogue of star clusters shown on Franklin-Adams chart plates. Mem.R.A.S., 60(5), 175-186.

Raab, S. (1922)

Raab, S. (1922) A research on open clusters. Lund Medd. Astron. Obs. Ser. II, 28, 1.

Discussed, based of F-A plates.

Doig, P. (1925)

Doig, P. (1925) Notes on the nebulae and clusters in Webb's 'Celestial Objects for Common Telescopes' (Sixth edition, Vol.ii). Part IV. M.N.R.A.S., 36(2), 58.

Trumpler, R.J. (1928)

Trumpler (Lick Obs Bul, Vol 14, No. 420) gives the diameter as 4.5' and the class as 1 2 r.

Bailey, S.I. (1908)

"cluster, fairly condensed, in one of the richest regions of the MilkyWay"

Bailey, S.I. (1908) A catalogue of bright stars and nebulae. Ann.Harv.Coll.Obs., 60(8), 199.

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a 11.5 mag open cluster.

Modern observations

Harrington, Phil

Phil Harrington (Sky&Telescope, July, 1992) writes: "... NGC 6603 appears as a rich, albeit faint, glow measuring 5' across and accented with a few feeble points of 14th mag light. Although most definitely an open cluster, the misty appearance of NGC 6603 has led more than a few observers to believe it's a globular. Only after closer examination with higher magnifications and larger apertures will the true nature of NGC 6603 be revealed."

Ware, Donald J

Donald J. Ware:"Has sometimes been erroneously identified as M- 24. This cluster is a small and tightly gathered grouping of stars which is best seen through a telescope."

Steve Coe

Steve Coe, observing with a 13" f/5.6, notes: "Bright, pretty large, very rich, very compressed, 33 stars counted at 165X. Nice reddish-orange 10th mag star on south side."

Contemporary observations

Magda Streicher

1997 August 05

12-inch Meade, 40mm eyepiece, 53' fov. 1997-08-05, fair sky conditions "Cluster easy visible with well condensed bright stars in an elongated haziness. Relatively rich and busy starfield." [Magda Streicher, Pietersburg 23-53S, 29-28E]

(no date)

12-inch f/10 SCT (EP: 2-inch 40mm SW 76x 53' fov; 2-inch 14mm UW 218x 23' fov)

Cluster easy visible with condensed faint stars in a slightly elongated northeast to south western direction and covered in haziness. Although if form part of the rich and busy Sagittarius Star Cloud it stands out well against the star-field. A few strings south can be seen running out into the field of view.

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