Small Cluster Nebula

History and Accurate Positions for the NGC/IC Objects (Corwin 2004)

NGC 7129 is a diffuse nebula enveloping three pretty bright stars. Both Herschels described it the same, and JH measured the position angles and distances of the two flanking stars with respect to the brightest, more central southern one, BD +65 1638. His mean position for the nebula, adopted in GC and NGC, is for that star.

Bigourdan apparently did not read JH's 1833 description before he examined the area in the 1884, 1889, and 1895. Bigourdan applied NGC 7129 only to the patch of nebulosity to the northwest of JH's star C, the northeastern of the three stars. He also found a "new" nebula in 1895 around JH's star A, the south-central of the three. This now carries the number IC 5134 (which see). Another "nova" from Bigourdan, NGC 7133 (which see), was apparently an illusion as there is nothing near his place but faint stars.

Historical observations

William Herschel (c.1784)

Synonyms: H IV-075

Discovered in 1794 by William Herschel with an 18.7-inch f/13 speculum telescope. He called it "three stars about 9m involved in nebulosity. The whole takes up a space of about 1.5' diameter; other stars of the same size are free from nebulosity."

NGC/IC Dreyer (1888, 1895, 1908)

"remarkable, considerably faint, pretty large, gradually brighter in the middle, triple star involved."

Published comments

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

Ced 196 (NGC 7129)

Position (1900): RA 22 40.7, Dec + 65 39

Star: Anon (Mp=10.5, V=10.3, SpT=B6)

Spectrum of nebula: continuous spectrum (inferred from sp.t. of illuminating star)

Classification: Neb associated with mainly one star (which may be multiple) - star surrounded by a neb envelope with conspicuous structure (eg. IC 5146)

Size: 7.5'x7'

Notes: "NGC 7129 = GC 4702 = h 2131 = H IV 75. Disc. 1792. (114, 194, 196, 208, 216, 217, 304, 366, 486, 549, 578, 608, 615 Pl 9, 631). R. The cluster contains the BD stars: +65 1631, 1633, 1635-1638, which are not in the HD catalogue. NGC 7133 is probably a part of this nebula. Alternative Class: A. 1."

Dorschner & Gürtler (1963)

Untersuchungen uber Reflexionsnebel.

DG 176 = NGC 7129, Ced 196

Pos (1950.0) 21:41.9, +65:53

Size: 8x6 (blue), 5x5 (red).

Lynds, B.T. (1965)

(Astrophysical Journal Supplement, No 105, 1965) in her Catalogue of Bright Nebulae notes that this isolated nebula is very bright, equally prominent on the red and blue POSS plates and has a maximum size of 2' x 2'.

Bernes, C. (1977)

Bernes, C. (1977) A catalogue of bright nebulosities in opaque dust clouds.

describes it as a reflection nebula, very bright on the blue plates, measuring 4' x 5'. The associated open cluster spans 2.7', contains 10 stars and has an integrated magnitude of 12.0. The cluster appears more like a star field concentration, and has a medium range in the brightness of the member stars.

Sulentic & Tifft (1973)

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

Lynds, B.T. (1962)

Lynds, B.T. (1962) Catalogue of dark nebulae. Astrophys.J.Suppl.Ser. 7, 1-52. [also: computer datafile: VII/7A]

Photo index

by Jim Lucyk: Vehrenberg's Atlas of Galactic Neb-2 p126.

Modern observations

Rajanen, Petteri (1992)

(Kauppi, Tampere, Finland) observing with a 8-inch f/5, writes in the The Webb Society Nebulae and Clusters Section Report No. 10, July 1992: "Observed with a Lumicon Deep-Sky filter. The associated cluster is very poor but bright, the surrounding nebula being of rather high surface brightness. Brightest portion is on NE side, with sharp edges. Clearly seen without filter. Overall shape somewhat rectangular."

Tom Lorenzin

Lorenzin, in the e-version of "1000+ The Amateur Astronomers' Field Guide to Deep Sky Observing", notes: "11.5M; Nebulosity surrounds four 10.5M stars; 5th star to NE = 12.5M; all 5 embedded in soft glow; two S-most aligned N-S; two N-most aligned WNW-ESE; nebulosity greatest around N-most, brighter pair; includes DIF NEB N7133; 20' NW of cluster N7142."

Brian Skiff

NGC 7129 & N7133

6cm - -29 seen as two dbl *s w/neb. brtst part of neb is around & N of Nrn pair. -33 is just NE, 1' diam, a faint splotch w/o *s.

15cm - consp neb oval elong E-W, 3'x2', overlying four *s in diamond, brtst is m8 on S. neb brtst nr vf * or knot on N side. a few other brtr *s in 15' area, hardly a cl. no neb around two *s NW of main grp. SW 15' is poor wkly concen cl of rel br *s. is there ID problem here in L&S, RNGC, etc? BS, 8Sep1991, Anderson Mesa.

25cm - nebulous cl w/four br *s & several fntr ones. neb around two cen *s, 4'x2'. fairly hisfcbr.

30cm - two pairs: Srn one in pa0, Nrn pair in pa110. neb is vbr around Ern member of Nrn pair & perhaps that * has f comp. neb mostly N of this pair w/two more *s inv, one vf. 2' irreg diam, bears magnification well. -33 is inv w/one * on its S side. 1' diam, fntr than -29.