Rho Ophiuchi Nebula (IC 4604)

Ophiuchus Molecular Cloud
Ophiuchus Molecular Cloud: Star forming region with open cluster Collinder 302 with Ophiuchus molecular cloud (Antares Nebula vdB 107, nebula IC 4603, ρ Ophiuchi nebula IC 4604, nebula IC 4605, Sharpless 2-9, many dark clouds), plus globular clusters M 4 and NGC 6144. North is left; Canon EOS 20Da, zoom lens 131 mm f:5.6 ; 145 min @ ISO 1600; Astrofarm Tivoli, Namibia, 1345 m ü. M.; © 5. 6. 2011 Eduard von Bergen, Hansjörg Wälchli [29]
IC 4592
IC 4592: Blue Horsehead Nebula (IC 4592), Rho Ophiuchi Nebula Complex (IC 4603-04-05-06, Sh 2-9), B 44, M 4, M 80, NGC 6144 and planet Mars (in Sco) and Saturn (in Oph); Carl Zeiss Apo Sonnar T* 135 mm f/2.0 ZE at f/2.8; Canon EOS 6Da; 21x5 min; ISO 800; Namibia, Tivoli Southern Sky Guest Farm, 1360 m ASL; © 29. 8. 2016 Manuel Jung [45]

Object Description

IC 4604
IC 4604: Reflection nebula around star ρ Ophiuchi. Crop from DSS [147]

The reflection nebula IC 4604 (LBN 1111) belongs together with IC 4603, IC 4605, the Antares nebula vdB 107, Sharpless 2-9 and many dark clouds to a large area of nebula, the Ophiuchus Molecular Cloud. Its center is about one degree south of the star ρ Ophiuchi, is surrounded by dense dust and is only visible in infrared images. The IC numbers were discovered in 1882 by the American astronomer Edward Barnard, who also recorded the dark clouds B 42, B 44 and B 45. [196, 239, 270, 277]

Rho Ophiuchi cloud complex
Rho Ophiuchi cloud complex: In visible light (DSS) and Infrared (WISE) [147]

The Ophiuchus Molecular Cloud, also called Rho Ophiuchus Cloud, is an area with active star formation, which is one of the closest to us at a distance of only about 407 light years. X-ray and infrared observations revealed more than 300 young stars within the large cloud in the center. The age of these stars is estimated to be only 300,000 years - very young compared to the oldest stars in the universe, which are more than twelve billion years old. [460]

Revised+Historic NGC/IC Version 22/9, © 2022 Dr. Wolfgang Steinicke [277]
Designation IC 4604
Type RN+*
Right Ascension (J2000.0) 16h 25m 33.0s
Declination (J2000.0) -23° 26' 36"
Diameter 60 × 50 arcmin
Metric Distance 0.120 kpc
Dreyer Description ρ Ophiuchi in eL neb
Identification, Remarks LBN 1112; ESO 517-*N3; CED 131B; Rho Oph nebula

Finder Chart

The nebula IC 4604 is located in the constellation Ophiuchus (Serpent Bearer) and as the name «Rho Ophiuchi nebula» suggests at the 5 mag star ρ Ophiuchi, around three degrees north of the bright star Antares (α Scorpii) in the constellation Scorpius (Scorpio). The best observation time is March to August.

Finder Chart Rho Ophiuchi Nebula (IC 4604)
Rho Ophiuchi Nebula (IC 4604) in constellation Ophiuchus. Charts created using SkySafari 6 Pro and STScI Digitized Sky Survey. Limiting magnitudes: Constellation chart ~6.5 mag, DSS2 close-ups ~20 mag. [149, 160]

Objects Within a Radius of 15°