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NGC 7423 (17,449 of 18,816)

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NGC 7423

NGC 7423, C 2253+568, Cl Berkeley 57, Ocl 246, III 745, h 2191, GC 4866

RA: 22h 55m 8s
Dec: +57° 05′ 54″

Con: Cepheus
Ch: MSA:1070, U2:58, SA:3

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

(reference key)

Type: open cluster, 22m

Mag: B=?, V=15

Size: 5′
PA: ?

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

NGC 7423 is a nice, compressed cluster at the NGC position. It sits between two brighter stars, and would probably be an interesting, if faint, object at the eyepiece.

JH was not sure in his 1833 catalogue if this was his father's III 745 or not. When he compiled the GC, however, he adopted his own position and his father's description. This is actually the best combination as both are correct. WH's position, however, is a minute of time east of the JH's position. Dreyer noticed this when he published all of WH's papers in 1912, and wrote a short note about it. In that note, Dreyer also mentions "In the sweep a star 6 mag = +56 2923 is 3m 41s f, 10' s." Doing the math from WH's reference star (Delta Cephei) for III 745, the BD star ends up close to its true position -- but III 745 is stubbornly 1 minute of time off.

Curiously, RNGC calls the cluster non-existent though it is clear on the POSS, and is included in the cluster catalogues as Berkeley 57 (that identity was apparently first noticed by Alister Ling in 1985). SIMBAD mistakenly equates the cluster with a faint planetary (an infrared source) a few arcmin to the northeast.

Historical observations

William Herschel (c.1784)

Synonyms: H III-745

Discovered in 1788 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "vF, pL, iF, easily resolvable."

Published comments

Sulentic & Tifft (1973)

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

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