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NGC 6401 (14,595 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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NGC 6401

NGC 6401, Ced 149, C 1735-238, ESO 520-11, GCl 73, I 44, h 1982, h 3697, GC 4314

RA: 17h 38m 36.93s
Dec: −23° 54′ 31.5″

Con: Ophiuchus
Ch: MSA:1394, U2:338, SA:22


(reference key)

Type: globular cluster

Mag: B=11.31, V=10.71

Size: 4.8′
PA: ?

Historical observations

William Herschel (c.1784)

Synonyms: H I-044

Discovered in 1784 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "cB pL Has a nucleus."

John Herschel (1847) Cape Observations

Observed by Sir John Herschel at the Cape of Good Hope with an 18-inch f/13 speculum telescope. He recorded it as "pB, R, vgbM, 25 arcseconds, a star 13m involved, following the centre." On a second occassion he called it "pB, R, vgbM, 2'; has a star 11m, rather following the middle."

Published comments

Helwan Obs. Bulletin No 9 (1912)

F, pS, an indefinite mass in the preceding side of a small cluster of very faint stars, among which the star mag 12 lies; possibly only a denser poriton of the cluster and not nebulous. Scheiner gives its spectrum as gaseous without reference to authority. It is very fain to have been observed spectroscopically, but if nebulous it is from its appearance probably gaseous.

Helwan Obs. Bulletin No 38 (1935)

Sparse cluster of f stars 3' in diameter much condensed at centre, rich field of f. stars.

Cederblad, S. (1946) [VII/231]

Ced 149 (NGC 6401)

Position (1900): RA 17 32.5, Dec - 23 51

Star: Anon (Mp=12.5:, V=12.8:)

Spectrum of nebula: (not classified)

Classification: Neb associated with mainly one star (which may be multiple) - star surrounded by a neb envelope without conspicuous structure (eg. lambda Scorpii)

Size: 1.5'x1.5'

Notes: "NGC 6401 = GC 4314 = h 1982 = h 3697 = H I 44. Disc. 1784. (93 Pl 21, 114). R. The nebula has also been listed as -23 13481."

Sulentic & Tifft (1973)

The RNGC (Sulentic and Tifft 1973) notes that this is a globular cluster.

Harris, W.E. (1997)

RA 17 38 36.9 (2000) Dec -23 54 32 Integrated V magnitude 9.45 Central surface brightness, V magnitudes per square arcsecond 18.67 Integrated spectral type F9 Central concentration, c = log(r_total/r_core); a 'c' denotes a core-collapsed cluster 1.69 Core radius in arcmin .25. ["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) ]

Modern observations

Tom Lorenzin

Tom Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "11M; 1' diameter; bright and round with little brighter center; unresolved; 13M star 7" SE of core."

Steve Coe

Steve Coe, using a 13" f/5.6, notes: " Pretty bright, pretty small, little brighter in the middle and very grainy at 220X. There is an 11th mag star on the east side. The cluster grows with averted vision and two stars are resolved across the face of this globular."

Contemporary observations

Tom Bryant

2009 9 13 21:56:8

Observing site: Pinnacles overlook

Telescope: C-11

[17h 38m 36s, -23 55' 0"] A faint cluster, very close to the horizon. Tonight's seeing is terrible, there is a wind gusting to 15mph. I could not resolve any stars. There is a 10mv foreground star (HD 160023) on the cluster's SE edge. It is unlikely I would have resolved it anyway, as the brightest stars come in at 16 mv.

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