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NGC 7790 (18,113 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 7790

NGC 7790, Cl Collinder 461, C 2355+609, Ocl 276.0, Ocl 276, COCD 520, VII 56, h 2285, GC 5032

RA: 23h 58m 24.2s
Dec: +61° 12′ 30″

Con: Cassiopeia
Ch: MSA:1069, U2:15, SA:3

Ref: NGC/IC, DAML02, Archinal&Hynes (2003)

(reference key)

Type: open cluster, 22m

Mag: B=9.18, V=8.5

Size: 5′
PA: ?

Historical observations

William Herschel (c.1784)

Synonyms: H VII-056

Discovered in 1788 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "a pretty compressed cluster of small stars of several sizes, considerably rich, E near the parallel, 5 or 6' long."

Published comments

Trumpler, R.J. (1928)

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

Phelps & Janes (1994)

Phelps and Janes give the outer cluster radius as 3.57arcminutes and list the minimum number of cluster members as 160. They include a plotted image of the cluster. [Phelps, R. L. & Janes, K. A. (1994) "Young Open Clusters as Probes of the Star Formation Process. 1. An atlas of open cluster photometry" Astrophys. J. Suppl. Series, 90:31-82.]

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a 7.0 mag open cluster.

Photo index

NGC 7790 Photo Index by Jim Lucyk: Deep Sky #10 Sp85 p2.

Modern observations

Ancient City Astron.Club (1980)

Listed by the Herschel Club, described as "some 25 stars counted in this cluster, large, somewhat scattered and circular. Number of stars faint overall, hint of some nebulosity. 8-inch, 48x."

Brian Skiff

POSS: can't see 30cm grp of *s in line on N.

WDS: CE Cas = Leonard 55: 10.9,11.1; 2".3; 266.

15cm - m9 * on SE, a few brtr cl members on NW side of cl. rectangular haze, a

doz *s. a clump of *s on E side. Roof.

- 12-15 *s. BS, 2Nov1980, Anderson Mesa.

- somewhat better still than -88. oval grp 5'x2'.5 elong E-W w/30 *s incl

three brtr *s rounding off W end. twd E side is tight clump incl at least

one dbl. most *s m12.5+. BS, 12Oct1990, Anderson Mesa.

25cm - sm, compact cl 4' diam w/circlet of br *s on W side. 25 *s w/some haze.


- 190x: 25 *s in 4'x2' area. five brtr *s on W side w/a few others.

condensed clump of m12-13 *s on E, incl m12 pair just res @ 190x. on E

border is arc opening E. BS, 2Nov1980, Anderson Mesa.

30cm - 220x: a cl E of three m8.5 *s. not faint. 20 *s fntr than m9.5. on N are

three brtst lined up SE-NW. f arm extends S and E. overall diam 2'.5.

Tom Lorenzin

Tom Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "9M; 5' diameter; 25-plus 11M and dimmer members; rich and compressed group; brighter stars to W of center; knot of dimmer stars E of center; 10' to NNW is cluster N7788 (10M; 3' diameter) small and rich group of 20-plus members amid larger field of brighter stars; one bright foreground star."

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