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Type: galaxy, Sa
Mag: B=11.9, V=?
Size: 3.019′ x 2.754′
Synonyms: H II-767
Discovered in 1788 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "pB, pL, R, vgmbM."
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).
The RNGC (Sulentic and Tifft 1973) notes that this is a 12.5 mag galaxy. Their coded description reads R,SLDIF,SO),SMBM.
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]
Sandage and Tammann (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.
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.
15cm - not vis.
- sm, fairly f gx SE of m11.5 *. circ w/nuch brtr center. 1' diam.
- mod f, consp @ 50x nr wide pair (m10,11) on N side. 165x: diam ~2.5x
sep of pair, halo circ. core distinctly outlined, seems barred, elong
NE-SW. somewhat mottled texture. BS, 29Jun1992, Anderson Mesa.
25cm - seen @ 47x, obvious @ hix. 1' circ shape, mod diffuse edge. *ar nuc vis
during good seeing.
- m11.5 * has m12.5 comp E. poss elong pa30. vmuch brtr cen, not *ar.
just a little brtr view from 15cm.
30cm - mod concen w/br center. *ar nuc seems to have spots around it. 220x
shows it in pa120, 1'.75x1', circ core 40" across. smooth except for
sparkles around nuc. un= pair 2' NW.
The Messier objects
The Bennett objects
The Caldwell list
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