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NGC 7243 (17,124 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 7243

NGC 7243, Cl Collinder 448, C 2213+496, Ocl 221.0, COCD 504, Caldwell 16, VIII 75, h 2155, GC 4773

RA: 22h 15m 6s
Dec: +49° 54′ 0″

Con: Lacerta
Ch: MSA:1103, U2:87, SA:9

Ref: SIMBAD, Collinder (1931), DAML02, Archinal&Hynes (2003)

(reference key)

Type: open cluster, 22m

Mag: B=6.54, V=6.4

Size: 29′
PA: ?

Historical observations

William Herschel (c.1784)

Synonyms: H VIII-075

Discovered in 1788 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "a cluster of coarsely scattered large stars, lE sp-nf, 16' long."

Published comments

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 II. M.N.R.A.S., 35(8), 280.

Vorontsov-Velyaminov, B. (1925/1926)

Vorontsov-Velyaminov, B. (1925) "Catalogue of integrated magnitudes of star clusters", Astron. Nach. 226.195. Comparing the brightness of the cluster with the extrafocal images of stars, he estimates the magnitude as 7.41.

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a 6.5 mag open cluster.

Trumpler, R.J. (1928)

Trumpler (Lick Obs Bul, Vol 14, No. 420) gives the diameter as 21' and the class as 3 2 p.

Photo index

Photo Index by Jim Lucyk: Deep Sky #1 Wi82 p18.

Melotte, P.J. (1915)

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

Modern observations

Sagot & Texereau (1964)

According to Sagot and Texereau, the cluster appears triangular in a 3.8-inch refractor at 45x. . the number of stars increases from 15 in a 2-inch to 60 in an 8-inch.

Hartung, E.J. (1968)

Hartung notes: "In a fine field this irregularly scattered cluster of moderatly bright stars without much concentration and about 20' across is fairly effective with small apertures."

Walter Scott Houston

Houston, observing with a 12-inch reflector could see no definite shape, but noted at least 80 stars within the cluster. He advises to look for a wide double star at the centre of the cluster, adding that it should be visible in a 6-inch or larger. He calls it a 7th mag cluster about 20' in diameter which is distinct against the star-studded Milky Way.

Ancient City Astron.Club (1980)

Listed by the Herschel Club, described as "50 stars counted in thsi loose and rather scattered grouping of stars. 8-inch, 48x."

Tom Lorenzin

Tom Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "8M; 20' diameter; 40-plus members includes DBL ST Struve 2890 (10" separation; both 8.5M)."

Brian Skiff

WDS: pair = ADS15785: 9.3,9.5; 9".3; 11.

POSS: blank area (1990 15cm obs) is on due N side.

15cm - 20' diam. many br *s. four sections. curls from E to S then N, like backwards C. 40 *s. HM, Roof.

- lg widespread cl w/little concen that only just stands out @ 50 from excellent Milky Way fld. roughly triangular 15' on-a-side: one apex points E, where a clump of *s is; at SW apex is rel wide m9 pair. nr center is rel close (15") m9.5-10 pair. cannot trace outliers beyond 20' diam---essentially the circle circumscribing the triangle. 80 or 90 *s at 80x to threshold (m~14). rel blank area on NE base of triangle. BS, 14Sep1990, Anderson Mesa.

25cm - 90x: not distinctive from Milky Way. elong NE-SW, 20'x15'. grouped into two lobes w/dk lane btwn. each lobe 7' across w/30 *s. SW lobe contains nice pair, m9.5.

- parabola of *s opening N, incl nice pair (10,10.3; 10"; pa350, bluish) on E side of circlet. 25 *s in or inv w/circlet. E and N are another 40 *s, a little fntr. total diam 30'. BS, 30Aug1981, Anderson Mesa.

30cm - spills out of 22' fld, 25'x18' in pa60. irreg grpings incl one nice pair nr the center w/sl different colors, 10" sep. 80 *s counted, incl bkgrnd. NE part smlr, SW lgr.

Favourite lists

Lacaille's catalogue

The Messier objects

Dunlop's catalogue

The Bennett objects

The Caldwell list

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