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NGC 6643 (15,094 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 6643

NGC 6643, LEDA 61742, MCG+12-17-021, UGC 11218, GC 4415

RA: 18h 19m 46.58s
Dec: +74° 34′ 7.9″

Con: Draco
Ch: MSA:1054, U2:12, SA:3


(reference key)

Type: galaxy, Sc

Mag: B=11.8, V=?

Size: 4.677′ x 2.344′
PA: 38°

Historical observations

Denning, W.F. (1892)

Denning, W.F. (1892) Supposed variable nebulae. Astr. Nachr., No.3111.

Published comments

Sulentic & Tifft (1973)

(Sulentic and Tifft 1973) notes that this is a 12.5 mag galaxy. Their coded description reads S,EL,HISB,DIFKNPERIP.

Sandage & Tammann (1975)

Sandage, A. & Tammann, G. A. (1975) Steps toward the Hubble constant. V - The Hubble constant from nearby galaxies and the regularity of the local velocity field. ApJ, 196, 313-328. [1975ApJ...196..313S]

(1975, Astrophysical Journal, 196, 313-328) includes this galaxy in the NGC 6643 Group. Members include NGC 6217, NGC 6340, NGC 6412, NGC 6643 & NGC 6654.

Sandage, A. et al. (1975) Galaxies and the Universe

G. de Vaucouleurs ("Galaxies and the Universe", Chapter 14 - Nearby Groups of Galaxies) notes that the five brightest members of the NGC 6643 group are NGC 6643, NGC 6217, NGC 6340, NGC 6412 & NGC 6654. NGC 6503 is a foreground member, and NGC 6621 is a background member.

de Vaucouleurs, G. (1975)

de Vaucouleurs, G. (1975) Nearby groups of galaxies. In: Kuiper, G. (ed) Stars and Stellar Systems. Volume 9: Galaxies and the Universe. Chapter 14, p557.

Foreground NGC 6503; background NGC 6621.

Brightest members: 6643 ( B(0) = 11.97), 6217 ( B(0) = 12.17), 6340 ( B(0) = 12.21), 6412 ( B(0) = 12.62), 6654 ( B(0) = 12.80).

Photo index

by Jim Lucyk: Burnhams V2 p874, Hubble Atl.of Gal. (Sandage 1961) p35, Rev.Shapley-Ames Cat.of Bright Gal. (Sandage,Tammann 1981) p103.

Sandage, A. (1961) The Hubble Atlas of Galaxies

This galaxy appears on page 35 of "The Hubble Atlas of Galaxies" by Allan Sandage (1961, Washington, DC).

Modern observations

Tom Lorenzin

Tom Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "12M; 3'x 2' extent; see photo at HAG-35."

Brian Skiff

NGC: pa50.

Lick: pa40.

UGC: pa38.

POSS: pa40. *s 1'.9 W, 1'.6 NW; m14 * 1'.2 SW (maybe what 25cm saw?).

15cm - not really.

- f, makes sm triangle w/vf *s to W. elong NE-SW, 1' diam.

- mod br but modlosfcbr @ 80x, fairly lg. 2'.5x1' in pa35. length approx = sep of NEmost m12 * flanking gx on W and another * SW (see sketch in notes). broad concen, only vf inconsp *ar nuc. BS, 29Jun1992, Anderson Mesa.

25cm - 3'x1' in pa50. br w/mod diffuse edges. br diffuse glow core 45" across w/*ar nuc.

- elong NE-SW, 1'.5x1'. broad concen, no sharp center. occas br spot seen SW of geom center.

30cm - nice, broad & grainy @ 140x. f *ar nuc. 2'.5x1'.75 in pa30. 220x: mottled texture, up to 3'x1'.75 via f halo. two m12 *s nrby on W in same pa as gx. little concen.

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