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IC 4604 (13,715 of 18,816)


oc gc pln bn dn gx gxcl ast aka lost




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rho Ophiuchi Nebula

IC 4604, Bernes 155, Ced 131b, DG 139, LBN 1111, Magakian 666, VDB 106, rho Ophiuchi Nebula

RA: 16h 25m 33s
Dec: −23° 26′ 36″

Con: Ophiuchus
Ch: MSA:1397, U2:336, SA:22

Ref: [2003A&A...399..141M], Corwin (2004)

(reference key)

Type: reflection nebula

Mag: B=?, V=?

Size: 71′ x 71′
PA: ?

Image gallery

Photos  (1)

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

IC 4604. See IC 4591.

Published comments

Doig, P. (1925)

Journal BAA, 35, p159

Region of nebulosity near rho: Barnard observed regions of nebulosity here when comet-seeking, and Sir John Hersdchel and others had earlier noticed the starless fields in the vicinity. These vacancies are now known to be due to absorptive effect of dust and gas clouds, which, where excited to luminosity by the B-type stars hereabouts, make the luminous parts. The luminous nebula at rhop consists of two condensations about 30' apart, the eastern (and brighter) one surrounding the star. From the diminution in number of the B stars of about 6 mag., in this part of the sky, assumeddue to obscurtion by these clouds, Shapley has estimated a distance of 650-1000l.y. Pannekoek however, considers the distance to be 330-650l.y.

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

Ced 131b (IC 4604)

Position (1900): RA 16 19.6, Dec - 23 13

Star: -23 12861 (Mp=4.70, V=4.76, SpT=B2, B3)

Spectrum of nebula: continuous spectrum (observed)

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

Size: 124'x124'

Notes: "Ced 131 The nebula at {rho} Ophiuchi. Disc. Barnard 1895 (61). Ced 131 b = IC 4604. FA 60. (34, 61, 66, 68, 70, 74, 78, 79, 82, 84, 86, 88 Pl 36, 92, 93 P1 13, 294, 295, 339, 366, 482, 486, 528, 630 Pl 2 Pl 5, 689, 715, 716, 820). R. -23 12861 = HD 147933,4 = Boss 22078,9 = {rho} Ophiuchi."

Lynds, B.T. (1962)

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

Dorschner & Gürtler (1963)

Untersuchungen uber Reflexionsnebel.

DG 139

= IC 4604, Ced 131b

Pos (1950.0) 16:22.6, −23:20

Size: 71x71 (blue), 10x10 (red).

Bernes, C. (1977)

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

= Bernes 155

Magakian T. Yu. (2003)

= DG 139, [RK68] 79, VdB 106, Bernes 155, IC4604, GN 16.22.6, Ced 131b, Other designations: rho Oph

Class: C (reflection neb)

Comments: double star

Photo index

by Jim Lucyk: Deep Sky #7 Su84 p25 Vehrenberg's Atlas of Galactic Neb-2 p9, 10.

Photo index by Jim Lucyk: 4605, 4606 & Ced 130, Sky & Tel. 4/79 (cover), Sky & Tel. 4/81 p287, Sky & Tel. 6/82 p575, Sky & Tel. 7/70 p36, Sky & Tel. 7/74 p11, Sky & Tel. 10/86 p335, Astronomy mag. 1/84 (cover), Astronomy mag. 11/79 p23, Burnhams V3 p1669

Modern observations

Identification chart

Identification chart for the region around Antares Nebula and rho Ophiuchi

Steve Coe

Coe, using a 13" f/5.6, notes: "Faint, very, very large, irregular nebula with Rho OPH involved. This dim glow is best in the 10X50 binoculars. This entire system is on the edge of one of the largest dark nebulae in the skies. About one degree away to the northwest is the area William Herschel called " A Hole in the Heavens". This dark nebula is so thick that a large scope at 100X will not show one star. You must see for yourself how fascinating it is to be awash in the Milky Way one minute and in a complete void the next."

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