Rho Ophiuchi

{{Short description|Multiple star system in the constellation Ophiuchus}}

{{about|the star|the dark cloud star forming region|Rho Ophiuchi cloud complex}}

{{Starbox begin

| name = ρ Ophiuchi

}}

{{Starbox image

|image=

{{Location mark

|image=Ophiuchus constellation map.svg|alt=|float=center|width=280

|label=|position=right

|mark=Red circle.svg|mark_width=10|mark_link=Rho Ophiuchi

|x=750|y=870

}}

|caption=Location of ρ Ophiuchi (circled red)

}}

{{Starbox observe

| epoch = J2000.0

| constell = Ophiuchus

| ra = {{RA|16|25|35.11766}}{{cite journal|title=Validation of the new Hipparcos reduction|author=van Leeuwen, F.|display-authors=etal|journal=Astronomy and Astrophysics|volume=474|issue=2|pages=653–664|date=2007|arxiv=0708.1752|bibcode=2007A&A...474..653V|doi=10.1051/0004-6361:20078357|s2cid=18759600}}

| dec = {{DEC|-23|26|49.8150}}

| appmag_v = 4.63{{Cite journal|bibcode=2002yCat.2237....0D|title=VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system|volume=2237|last1=Ducati|first1=J. R.|journal=VizieR Online Data Catalog|year=2002}}

}}

{{Starbox character

| component1 = ρ Oph AB

| class = B2/3V + B2V{{cite book|bibcode=1988mcts.book.....H|title=Michigan Catalogue of Two-dimensional Spectral Types for the HD Stars. Volume 4, Declinations −26°.0 to −12°.0|last1=Houk|first1=N.|last2=Smith-Moore|first2=M.|year=1988}}

| b-v = +0.24{{cite journal|title=Catalogue of homogeneous data in the UBV photoelectric photometric system|date=1964|journal=Astronomy and Astrophysics Supplement Series|volume=34|pages=1–49|author=Nicolet, B.|bibcode=1978A&AS...34....1N}}

| u-b = −0.56

| variable =

}}

{{Starbox astrometry

| component1 = ρ Oph AB

| radial_v = {{val|−14.6|1.5}}

| prop_mo_ra = −5.53

| prop_mo_dec = −21.74

| pm_footnote =

| parallax = 7.19

| p_error = 0.13

| parallax_footnote =

| dist_pc = {{Val|138.2|3.6}}

| dist_ly = {{val|{{convert|138.2|pc|ly|disp=number}}|{{convert|3.6|pc|ly|disp=number}}|fmt=commas}}

| dist_footnote =

| absmag_v = {{val|-2.5|0.3}}{{cite journal|bibcode=2003AN....324..219W|doi=10.1002/asna.200310081|title=The total-to-selective extinction ratio determined from near IR photometry of OB stars|journal=Astronomische Nachrichten|volume=324|issue=3|pages=219–237|year=2003|last1=Wegner|first1=W.}}

}}

{{Starbox orbit

| primary = ρ Oph Aa

| name = ρ Oph Ab

| reference = {{Cite arXiv |last1=Klement |first1=R. |last2=Shultz |first2=M. E. |last3=Rivinius |first3=Th. |title=Spatially resolved centrifugal magnetosphere caught in motion around the secondary component of ρ Oph A |date=2025 |class=astro-ph.SR |eprint=2505.10038 }}

| period_unitless = {{Val|87.831|0.010}} days

| axis_unitless = {{Val|0.995|0.026|ul=AU}}

| eccentricity = {{Val|0.17931|0.00017}}

| inclination = {{val|71.348|0.020}}

| k1 = {{Val|55.5|3.6}}

| k2 = {{Val|65.7|3.6}}

| periarg = {{Val|4.80|0.24}}

| node = {{Val|303.385|0.034}}

| periastron = 60101.11 RJD

}}

{{Starbox orbit

| reference = {{cite journal|title=Orbits of Five Visual Binary Stars|author=Novaković, B.|journal=Baltic Astronomy|volume=16|pages=435–442|date=2007|bibcode=2007BaltA..16..435N|arxiv=0712.4242}}

| primary = ρ Oph A

| name = ρ Oph B

| period_unitless = {{val|2398|326|fmt=commas}} years

| axis = {{val|4.25|0.79}}

| eccentricity = {{val|0.675|0.322}}

| inclination = {{val|135.3|6.0}}

| node = {{val|77.5|13.5}}

| periastron = B {{val|2327|343}}

| periarg = {{val|226.1|15.3}}

}}

{{Starbox orbit

| reference =

| primary = ρ Oph D

| name = ρ Oph E

| period_unitless = {{val|675.5|32.5}} years

| axis = {{val|1.01|0.15}}

| eccentricity = {{val|0.707|0.112}}

| inclination = {{val|134.8|2.7}}

| node = {{val|152.7|4.6}}

| periastron = B {{val|2008.6|34.2}}

| periarg = {{val|260.4|1.1}}

}}

{{Starbox detail

| source =

| component1 = ρ Oph Aa

| mass = {{Val|9.21|0.79}}

| radius = {{val|4.2|0.3}}

| rotation = 1.205 days

| rotational_velocity = {{val|206|5}}

| luminosity = {{Val|4270|980|800|fmt=commas}}

| temperature = {{Val|23000|1000|fmt=commas}}

| gravity = {{Val|4.25|0.25}}

| age_myr = {{Val|15|6}}

| component2 = ρ Oph Ab

| mass2 = {{Val|7.79|0.70}}

| radius2 = {{Val|3.1|0.2}}

| luminosity2 = {{val|1000|400|290|fmt=commas}}

| temperature2 = {{val|19000|1000|fmt=commas}}

| gravity2 = {{Val|4.25|0.25}}

| age_myr2 = {{Val|15|6}}

| rotational_velocity2 = {{val|227|5}}

}}

{{Starbox detail | no_heading = y

| component1 = ρ Oph B

| mass = 8{{cite journal|doi=10.1093/mnras/sty2502|title=The dynamical evolution of multiple systems of trapezium type|year=2018|last1=Allen|first1=Christine|author1-link=Christine Allen (astronomer)|last2=Ruelas-Mayorga|first2=Alex|last3=Sánchez|first3=Leonardo J.|last4=Costero|first4=Rafael|journal=Monthly Notices of the Royal Astronomical Society|doi-access=free|arxiv=1809.03537}}

}}

{{Starbox detail | no_heading = y

| component1 = ρ Oph C

| mass = 5

}}

{{Starbox detail | no_heading = y

| component1 = ρ Oph D

| mass = 3.06

| component2 = ρ Oph E

| mass2 = 1.97

}}

{{Starbox catalog

| names = {{odlist|B=ρ Oph|F=5 Oph|WDS=J16256-2327}}

| component1=ρ Oph AB

| names1={{odlist|HIP=80473|CD=-23°12861}}

| component2=ρ Oph A

| names2={{odlist|HD=147933|HR=6112|SAO=184382}}

| component3=ρ Oph B

| names3={{odlist|HD=147934|HR=6113|SAO=184381}}

| component4=ρ Oph C

| names4={{odlist|HIP=80474|SAO=184383|CD=-23°12862}}

| component5=ρ Oph D/E

| names5={{odlist|HD=147888|HIP=80461|SAO=184377|CD=-23°12860}}

}}

{{Starbox reference

| Simbad=rho+Oph|sn=ρ Oph

| Simbad2=HD+147933|sn2=ρ Oph A

| Simbad3=HD+147934|sn3=ρ Oph B

| Simbad4=HD+147932|sn4=ρ Oph C

| Simbad5=HD+147888|sn5=ρ Oph D/E

}}

{{Starbox end}}

Rho Ophiuchi (ρ 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, it is located about 450 light-years distant. The other stars in the system are slightly farther away.{{clarify|reason=Slightly further away in distance from Earth or distance from the inner pair?|date=May 2025}}