Rho Ophiuchi is a multiple star
system in the constellation Ophiuchus. The central system has
an apparent magnitude of 4.63. Based on the central system's
parallax of 9.03 mas, it is located about 360 light-years (110
parsecs) away. The other stars in the system are slightly
farther away.
The
central pair is known as Rho Ophiuchi AB. It consists of at
least two blue-colored subgiants or main-sequence stars,
designated Rho Ophiuchi A and B, respectively.Rho Ophiuchi AB
is a visual binary, and the sky-projected distance between the
two stars appears to be 3.1″, corresponding to a separation of
at least 344 astronomical units (au). However, the actual
separation is larger, and the two take about 2,400 years to
complete an orbit. |