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RA: 17h 53m 12s
Dec: −22° 19′ 0″
Con: Sagittarius
Ch: MSA:1393, U2:339, SA:22
Ref: SIMBAD, Collinder (1931), DAML02, Archinal&Hynes (2003)
Type: open cluster, 42m
Mag: B=?, V=8.2
Size: 7′
PA: ?
Discovered by Sir John Herschel at the Cape of Good Hope with an 18-inch f/13 speculum telescope. He recorded it as "a pretty rich insulated milky way cluster; place of a course double star in it. The milky way hereabouts is very poor."
Trumpler (Lick Obs Bul, Vol 14, No. 420) gives the diameter as 15' and the class as 4 2 m.
Raab, S. (1922) A research on open clusters. Lund Medd. Astron. Obs. Ser. II, 28, 1.
Discussed, based of F-A plates.
The RNGC (Sulentic and Tifft 1973) notes that this is a 8.0 mag open cluster.
A catalogue of star clusters shown on Franklin-Adams chart plates. Mem.R.A.S., 60(5), 175-186.
Steve Coe, observing with a 13" f/5.6, notes: "Bright, pretty large, pretty rich and somewhat compressed, 26 stars counted at 100X. It can just be seen in the 11X80 finder. The observation above was from one of my best nights ever at the telescope. At a site with 7200 ft. of elevation in the Central Mountains of Arizona. I rated the night as 8/10 for seeing and 10/10 for contrast. On a much poorer evening on the desert floor only about 50 miles from Phoenix, I saw this cluster as: pretty faint, pretty large and not compressed, not much. What a difference a two hour drive makes!"
1998-07-31/08-01
Location: Jonkershoek Nature Reserve, Assegaaibosch Station
Date: 1998 July 31 / August 01, 01:00-02:40 SAST
11x80 tripod-mounted binoculars (9.5 mag stars at times not easy)
Sky conditions: Mediocre (transp. low, seeing average, dew) The skies are showing the effects of the combination of pollution (mainly from a nearby wood-processing plant) and a stable inversion layer, turning daytime skies grey-blue, and night skies ashen.
To the north-west of the Lagoon nebula. Binoculars show NGC 6469 as a delicate, vague round puff of soft light. Contains two small stars (east & south-east) to the side. A delicate object, needing care tonight but nevertheless found while sweeping.
Observing site: Little Tycho Observatory
Telescope: C-8
[17h 52m 54s, -22° 21' 0"] Around 6 10-12mv stars in a 10' field. Hardly stands out from the rest of the milky way, this hazy night. Confirmed: WikiSky.
Lacaille's catalogue
The Messier objects
Dunlop's catalogue
The Bennett objects
The Caldwell list
Named DSOs
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