HD 170469
{{Short description|Star in the constellation Ophiuchus}}
{{Starbox begin}}
{{Starbox observe
| epoch = J2000
| constell = Ophiuchus
| dec = {{DEC|+11|41|43.7985}}
}}
{{Starbox character
| type =
| u-b =
| variable =
}}
{{Starbox astrometry
| radial_v = {{Val|−59.32|0.10}}
| prop_mo_ra = {{val|−48.418|0.070}}
| prop_mo_dec = {{val|−17.470|0.079}}
| parallax = 16.5886
| p_error = 0.0408
}}
{{Starbox orbit
| primary = HD 170469
| name = HD 170469 B
| period = 114000
| period_unitless =
| axis = 43.1
| axis_unitless =
| eccentricity =
| inclination =
| node =
| periastron =
| periarg =
| periarg_primary =
| k1 =
| k2 =
}}
{{Starbox detail
| source =
| component1 = A
| luminosity = {{Val|1.639|0.006}}
| temperature = {{Val|5786|28|fmt=commas}}
| metal_fe = {{Val|0.28|0.02}}
| rotational_velocity =
| age_gyr = {{Val|4.8|3.0|0.5}} or {{Val|8.6|0.5}}
| component2 = B
}}
{{Starbox catalog
| names = {{odlist | B=t2 Car | BD=+11°3479 | HD=170469 | HIP=90593 | SAO=103765|2MASS=J18291097+1141437|Gaia DR2=4484013343859055744}}
}}
{{Starbox reference
| Simbad = HD+170469
}}
{{End}}
HD 170469 is a probable binary star system in the equatorial constellation of Ophiuchus. It is too faint to be viewed with the naked eye, having an apparent visual magnitude of 8.21. The system is located at a distance of 197 light years away from the Sun based on parallax. It is drifting closer with a radial velocity of −59 km/s, and is expected to come to within {{Convert|15.27|pc|ly|disp=out|abbr=off}} in about 959,000 years.
The primary, component A, is a G-type main-sequence star with a stellar classification of G5V, indicating it is generating energy through core hydrogen fusion. Estimates of the star's age range from five to almost nine billion years. It has 1.10 times the mass of the Sun and 1.24 times the Sun's radius. The star has a higher than solar metallicity. It is radiating 1.64 times the Sun's luminosity from its photosphere at an effective temperature of 5,786 K.
The secondary companion, component B, is located at an angular separation of {{Val|43.21|0.10|ul=arcsecond}} along a position angle of {{Val|112.55|0.07|u=°}} from the primary, as of 2018. Initially it was thought to be a red dwarf of spectral class M1, but was later determined to be a K-type main-sequence star with a class of K5V. This star lies at a projected separation of {{Val|2708|ul=AU}} from the primary, and is orbiting with an estimated period of around 114,000 years.
Planetary system
In 2007, a planet was discovered by the N2K Consortium, led by principal investigators Debra Fischer and Gregory P. Laughlin. It was spotted using the radial velocity method, and was independently confirmed in 2014.
{{OrbitboxPlanet begin
}}
{{OrbitboxPlanet
| exoplanet = b
| mass = >0.67
| period = 1,143
| semimajor = 2.24
| eccentricity = 0.11
}}
{{Orbitbox end}}
See also
References
{{Reflist|refs=
{{Cite Gaia DR2|4484013343859055744}}
{{cite simbad | title=HD 170469 | access-date=2018-07-13}}
| title=XHIP: An extended hipparcos compilation
| last1=Anderson | first1=E. | last2=Francis | first2=Ch.
| journal=Astronomy Letters | volume=38 | issue=5 | pages=331 | year=2012
| bibcode=2012AstL...38..331A | arxiv=1108.4971
| doi=10.1134/S1063773712050015 | s2cid=119257644 }}
| title=Calibrating the metallicity of M dwarfs in wide physical binaries with F-, G-, and K-primaries - I: High-resolution spectroscopy with HERMES: stellar parameters, abundances, and kinematics
| last1=Montes | first1=D. | last2=González-Peinado | first2=R.
| last3=Tabernero | first3=H. M. | last4=Caballero | first4=J. A.
| last5=Marfil | first5=E. | last6=Alonso-Floriano | first6=F. J.
| last7=Cortés-Contreras | first7=M. | last8=González Hernández | first8=J. I.
| last9=Klutsch | first9=A. | last10=Moreno-Jódar | first10=C.
| display-authors=1 | journal=Monthly Notices of the Royal Astronomical Society
| volume=479 | issue=1 | pages=1332–1382 | date=September 2018
| doi=10.1093/mnras/sty1295 | doi-access=free | arxiv=1805.05394
| bibcode=2018MNRAS.479.1332M | s2cid=119260219 }}
| display-authors=1 | last1=Stassun | first1=Keivan G.
| last2=Collins | first2=Karen A. | last3=Gaudi | first3=B. Scott
| title=Accurate Empirical Radii and Masses of Planets and Their Host Stars with Gaia Parallaxes
| journal=The Astronomical Journal
| volume=153 | issue=3 | pages=136 | year=2017
| arxiv=1609.04389 | doi=10.3847/1538-3881/aa5df3
| bibcode=2017AJ....153..136S | s2cid=119219062 | doi-access=free }}
| last1=Bonfanti | first1=A. | last2=Ortolani | first2=S.
| last3=Piotto | first3=G. | last4=Nascimbeni | first4=V.
| title=Revising the ages of planet-hosting stars
| display-authors=1 | journal=Astronomy & Astrophysics
| volume=575 | id=A18 | pages=17 | date=March 2015
| doi=10.1051/0004-6361/201424951 | arxiv=1411.4302
| bibcode=2015A&A...575A..18B | s2cid=54555839 }}
| last=Tokovinin | first=Andrei
| title=From Binaries to Multiples. II. Hierarchical Multiplicity of F and G Dwarfs
| journal=The Astronomical Journal
| volume=147 | issue=4 | pages=87 | year=2014
| arxiv=1401.6827 | bibcode=2014AJ....147...87T
| doi=10.1088/0004-6256/147/4/87 | s2cid=56066740
}}
| title=New wide stellar companions of exoplanet host stars
| display-authors=1 | last1=Mugrauer | first1=M.
| last2=Ginski | first2=C. | last3=Seeliger | first3=M.
| journal=Monthly Notices of the Royal Astronomical Society
| volume=439 | issue=1 | pages=1063–1070 | date=March 2014
| doi=10.1093/mnras/stu044 | bibcode=2014MNRAS.439.1063M | doi-access=free }}
| title=Five Intermediate-Period Planets from the N2K Sample
| last1=Fischer | first1=Debra A. | last2=Vogt | first2=Steven S.
| last3=Marcy | first3=Geoffrey W. | last4=Butler | first4=R. Paul
| last5=Sato | first5=Bun’ei | last6=Henry | first6=Gregory W.
| last7=Robinson | first7=Sarah | last8=Laughlin | first8=Gregory
| last9=Ida | first9=Shigeru | display-authors=1
| journal=The Astrophysical Journal
| volume=669 | issue=2 | pages=1336–1344 | year=2007
| doi=10.1086/521869 | arxiv=0704.1191
| bibcode=2007ApJ...669.1336F | s2cid=7774321 }}
}}
{{Ophiuchus}}
{{Sky|18|29|10.9812|+|11|41|43.7985}}
{{DEFAULTSORT:HD 170469}}
Category:G-type main-sequence stars
Category:K-type main-sequence stars
Category:Planetary systems with one confirmed planet