Rho Ophiuchi (ρ Ophiuchi) is a multiple star system in the constellation Ophiuchus.[1] It consists of at least two blue subgiants, ρ Oph A and ρ Oph B, both of which are of class B.[7] ρ Oph AB is a visual binary, and the sky-projected distance between ρ Oph A and ρ Oph B is 3.1" (or 344 AU at the 111 pc distance of ρ Oph AB).[7]
Two to three other blue subgiants, ρ Oph C and ρ Oph DE, are found to be related to the star system, with sky-projected distances to ρ Oph AB of ~ 17,000 and ~ 19,000 AU, respectively. ρ Oph C and ρ Oph D are also of class B.
The apparent brightness of the star system has been dimmed by about 2 magnitudes[citation needed], as a result of interstellar extinction, due to its location within the Ophiuchus cloud. The star system, ρ Oph AB, is located about 360 light years away.[2]
References
- ^ a b c d e f g h i j k l m "rho Oph, SIMAD".
- ^ a b c d e "van Leeuwen, F. 2007, Hipparcos, the New Reduction of the Raw Data".
- ^ a b c d e f g h i "Ducati, J. R. 2002, CDS/ADC Collection of Electronic Catalogues".
- ^ "rho Oph A, SIMBAD".
- ^ "rho Oph B, SIMBAD".
- ^ "Houk, N. and Smith-Moore, M. 1988, Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars. Volume 4, Declinations -26°.0 to -12°.0.".
- ^ a b c "Cordiner, M. A., Fossey, S. J., Smith, A. M. and Sarre, P. J. 2013, ApJ, 764, L10".