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NGC 6631 (15,144 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 6631

NGC 6631, Cl Collinder 379, C 1824-120, Lund 833, Ocl 59.0, h 3746, GC 4409

RA: 18h 27m 12s
Dec: −12° 02′ 0″

Con: Scutum
Ch: MSA:1343, U2:295, SA:15

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

(reference key)

Type: open cluster, 21m

Mag: B=?, V=11.7

Size: 6′
PA: ?

Historical observations

John Herschel (1847) Cape Observations

Discovered by Sir John Herschel at the Cape of Good Hope with an 18-inch f/13 speculum telescope. He recorded it as "cluster VII class, p rich, 5' diameter, with appendages, stars 12..15m. Much richer than any part of the mlky way seen to-night."

Published comments

Trumpler, R.J. (1928)

Trumpler (Lick Obs Bul, Vol 14, No. 420) gives the diameter as 4.5' and the class as 1 2 p.

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a 11.5 mag open cluster.

Modern observations

Brian Skiff

Pluto camera plate: 15/25cm pair: 12"; pa225.

15cm - some haze amongst 12-15 *s @ 150x. BS, 7Aug1980, Anderson Mesa.

- dbl * res. brtr *s at each end of elong grp. about 17 *s vis @ 125x. BS,

15Mar1981, Anderson Mesa.

- rel f cl but consp by being mostly surrounded by dk areas. res @ 80x.

140x: 6' diam w/15 *s res mostly m13+, but one m11.5 * on NW. broad

concen. in wk *ry band running NE-SW. BS, 21Jun1990, Anderson Mesa.

25cm - vis @ 50x, nice cl 6'-8' diam. *s scattered w/mild concen. about 30 *s

m11-14 incl m11.5 pair isolated on S side. BS, 7Aug1980, Anderson Mesa.

- 6'x3' in pa 150, 35 *s @ 190x. m11 * on NW end, M10.5 on SE end. pair:

11,11.5;10";pa230. BS, 15Mar1981, Anderson Mesa.

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