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NGC 603 (1,176 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 603

NGC 603, GC 357

RA: 01h 34m 44s
Dec: +30° 13′ 58″

Con: Triangulum
Ch: MSA:146, U2:91, SA:4

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

(reference key)

Type: stars (three)

Mag: B=?, V=14

Size: 0.2′
PA: ?

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

NGC 603 is a triple star found by Lord Rosse. It's position was unfortunately not well-determined, so there has been some puzzle over its identity. Dreyer, in the Notes to IC1, claimed that he could only see a faint star in the place of NGC 603. (I've been unable to identify this star with any certainty. One candidate is at 01 31 30.4, +29 55 58, B1950.0, while Bigourdan has two observations of another at 01 31 44.7, +29 56 42.)

However, Lord Rosse's description makes the identification certain, even without a good position: "A small nebula or cluster with 3 stars in it. It is about 8 arcmin south-southpreceding a double star whose components are of the 11th magnitude." This is very close to the actual distance of the double from the triple star -- but there is no nebulosity or cluster associated with the triple. I suspect that the discovery was made on a night of relatively poor seeing, leading to the impression of accompanying nebulosity.

The B1950.0 positions of the three stars, all from GSC, are

*1 01 31 54.54 +29 58 37.1 = GSC 02293-00972 *2 01 31 54.85 +29 58 45.4 = GSC 02293-00966 *3 01 31 55.37 +29 58 31.6 = GSC 02293-00998.

I've adopted the mean value for the main table.

Historical observations

Birr Castle/Lord Rosse

Observations with the 72-inch f/8.8 speculum telescope at Birr Castle: Announced this object on November 29, 1850, described as "a small nebula or cluster with 3 stars in it."

Published comments

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a nonexistent object. Their coded description reads KN IN 598 ZWICKY.

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