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RA: 16h 46m 58.86s
Dec: +47° 31′ 40.1″
Ch: MSA:1117, U2:80, SA:8
Ref: SIMBAD, SEDS
Type: globular cluster
Mag: B=9.38, V=9.39
Synonyms: H IV-050
Discovered in 1787 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "vB, R, 4' diameter, almost equally bright, with a faint resolvable margin."
In the 5th edition of Webb's Celestial Objects for Common Telescopes it is described as "planetary nebula, faint with 3.7-inch, but beautifully grouped in a triangle with two 6th mag stars. D'Arrest, very crowded cluster."
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.
"globular cluster? extremely condensed, not resolved on Bruce plate"
Bailey, S.I. (1908) A catalogue of bright stars and nebulae. Ann.Harv.Coll.Obs., 60(8), 199.
A catalogue of star clusters shown on Franklin-Adams chart plates. Mem.R.A.S., 60(5), 175-186.
Table, p.177: "Clusters" noted by Bailey but not included in the Catalogue:
"NGC 6229: Appears as a bright nebulous star."
p.178: "Six clusters noted in Lick Obs. Bull., No.219 (Descriptions of 132 Nebulae and Clusters photographed with the Crossley Reflector) are not included in the catalogue.
NGC 6229: Appears as a bright nebulous star.
The RNGC (Sulentic and Tifft 1973) notes that this is a 10.5 mag globular cluster.
RA 16 46 58.9 (2000) Dec +47 31 40 Integrated V magnitude 9.39 Central surface brightness, V magnitudes per square arcsecond 16.99 Integrated spectral type F7- Central concentration, c = log(r_total/r_core); a 'c' denotes a core-collapsed cluster 1.61 Core radius in arcmin .13. ["Catalog Of Parameters For Milky Way Globular Clusters", compiled by William E. Harris, McMaster University. (Revised: May 15, 1997; from http://www.physics.mcmaster.ca/Globular.html; Harris, W.E. 1996, AJ, 112, 1487) ]
Hartung notes: "The low elevation of this northerlyglobular at culmination, for most southern observers, demands a good clear horizon. 30cm shows me a bright round symmetrical haze about 1' across, rising much to the centre and with an occassional sparkle indicating resolution. This object is plain with 10.5cm, forming a triangle with two bright stars."
Houston wrote in 1976: "In Herucles is one of William Herschel's few mistakes. Herschel thought this was a planetary nebula, but today we know it as a globular. The deception results from its small size (1.2') and considerable brightness (mag 8.7). In big binoculars, it appearws to be just another star, and in my 4-inch Clark it does look like a planetary, except that the characteristic greenish tint is lacking."
Darren Bushnall (Hartlepool, Cleveland) observing with a 8.5-inch f/6, writes in the The Webb Society Nebulae and Clusters Section Report No. 11, January 1993: "The third globular in Hercules, easily visible at low power as a small, circular glow east of two mag 8 stars. At x180, moderately bright and large with a bright core enveloped in a soft haze about 1' in diameter. Using averted vision, NGC 6229 is granular; some resolution suspected."
Observer: John Callender
Instrument: 8-inch Dobsonian reflector Location: Carpinteria, CA, USA
Light pollution: light Transparency: good Seeing: fair
Time: Sun Jun 29 09:20:00 1997 UT Obs. no.: 167
An easy, small, round fuzzy patch, with a denser core, at 49x. I was unable to resolve it into stars at either 122x or 244x. Per
Burnham's, m8.7, diam 3.5'.
Your skills: Intermediate (some years)
Sky darkness: 5.2 Limiting magnitude
Seeing: 7 1-10 Seeing Scale (10 best)
Moon presence: None - moon not in sky
Instrument: Ultima C-8 PEC w/ 80mm f/10 MAK
Small, compact, Bright. Some stars resolved starting at 127x. Stellar with the 80mm.
Tom Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "8.7M; 3.5' extent; bright but unresolved at >200x; interesting glow with bright center; 7.5M star 6' W; 8M star 6' SW."
15cm - sm, br, hisfcbr glow making triangle w/two m7 *s W. 165x shows it wkly
gran, 2'.5-3'. 295x: exf vfine gran to the halo, perhaps 20 *s res with
impression of many more. circ, mod-strong even concen. BS, 4Jul1989,
25cm - 1'.5 diam. lies E of wide pair. 180x shows only gran.
- pretty sm, 0'.8 diam. wkly textured @ 280x. core 20" across, smoothly
brtr. BS, 23May1982, Anderson Mesa.
30cm - 147x: fairly sm. broad concen not res: gran, but not sparkling. 2' diam,
Bright, prominent globular cluster, approximately 4 arc minutes in diameter, with a distinct rough-textured appearance caused by its faint stars. Somewhat hazy to the outer edges; the centre appears only slightly brighter. Two bright (about 8th magnitude) white stars make a distinct triangle with the globular; visible in the same field to the west is a half-moon of stars arranged somewhat around the triangle.
Alldays (22.50S, 20.12E, 770m).
12-inch f/10 SCT (218x, 346x)
Bright, prominent round globular cluster with somewhat hazy outer edges, the broad center appears only slightly brighter with perhaps some resolution suspected. Third globular in Hercules, easily visible at low power as a small, circular glow east of two white 8 magnitude stars which make a distinct triangle with the globular. To the west is a half-moon of stars arranged somewhat around and a triangle. One of William Herschel's mistakes he thought this was a planetary nebula, but today we know it as a globular. It looks like a planetary except that the characteristic greenish tint is lacking. Very Small strong light point nucleus, no stars very strong light point. The deception results from its small size and considerable brightness. It looks like a planetary, except that the greenish tint is lacking. Very Small strong nucleus, no stars very strong light point, but expect granularity.
Observing site: Little Tycho Observatory
[16h 47m 0s, 47° 32m 0s] Looks like a bright elliptical galaxy. There was the slightest bit of mottling in the cluster, visible with averted vision and 163x. It looked more condensed than its class VII type indicates. Early observers (Herschel, Webb) saw this as a planetary nebula. The brightest stars are reported as 15.5 Mv, it's not suprising that I didn't resolve this one!
The Messier objects
The Bennett objects
The Caldwell list
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