HD 117618

{{short description|Star in the Centaurus constellation}} {{Starbox begin | name = HD 117618 / Dofida }} {{Starbox observe | epoch = J2000 | constell = [[Centaurus]]<ref name=Anderson2012/> | ra = {{RA|13|32|25.55562}}<ref name=dr3/> | dec = {{DEC|−47|16|16.9132}}<ref name=dr3/> | appmag_v = 7.17<ref name=Anderson2012/> }} {{Starbox character | type = [[main sequence]]<ref name=dr3/> | class = G0 V<ref name=Gray2006/> | b-v = {{Val|0.603|0.010}}<ref name=Anderson2012/> | u-b = }} {{Starbox astrometry | radial_v = {{Val|+1.60|0.76}}<ref name=Anderson2012/> | prop_mo_ra = +25.214<ref name=dr3/> | prop_mo_dec = −125.428<ref name=dr3/> | parallax = 26.5429 | p_error = 0.0214 | parallax_footnote = <ref name=dr3/> | absmag_v = 4.27<ref name=Anderson2012/> }} {{Starbox detail | source = <ref name=Bonfanti2016/> | mass = {{Val|1.10|0.02}} | radius = {{Val|1.17|0.04}} | luminosity = {{Val|1.6|0.1}} | gravity = {{Val|4.34|0.03}} | temperature = {{Val|6019|50|fmt=commas}} | metal_fe = {{Val|+0.03|0.01}}<ref name=Adibekyan2016/> | rotational_velocity = 3.67<ref name=Delgado_Mena2015/> | age_gyr = {{Val|4.0|1.3}} }} {{Starbox catalog | names = {{odlist | name=Dofida | CD=-46°8708 | HD=117618 | HIP=66047 | SAO=224228 | GC=18290 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad = HD+117618 | NSTED = HD-117618 }} {{Starbox end}}

'''HD 117618''', named '''Dofida''' by the [[IAU]],<ref name="IAU Approved"/> is a single,<ref name=Raghavan2006/> yellow-hued [[star]] in the southern [[constellation]] of [[Centaurus]]. With an [[apparent visual magnitude]] of 7.17,<ref name=Anderson2012/> it is too faint to be visible to the naked eyes of a typical observer. The distance to this star, as determined from its annual [[stellar parallax|parallax shift]] of {{Val|26.54|ul=mas}} as seen from Earth's orbit,<ref name=dr3/> is 123 [[light year]]s. It is moving further away with a heliocentric [[radial velocity]] of around +1.6 km/s.<ref name=Anderson2012/>

This star is similar to the [[Sun]], being a [[G-type main-sequence star]] with a [[stellar classification]] of G0 V.<ref name=Gray2006/> It is about 10% more massive and 17% larger than the Sun, with an estimated age of roughly four billion years<ref name=Bonfanti2016/> and a [[projected rotational velocity]] of 3.67 km/s.<ref name=Delgado_Mena2015/> The star is radiating 1.6 times the [[Sun's luminosity]] from its [[photosphere]] at an [[effective temperature]] of 6,019 K.<ref name=Bonfanti2016/>

==Name==

HD 117618, and its planet HD 117618b, were chosen as part of the 2019 [[NameExoWorlds]] campaign organised by the [[International Astronomical Union]], which assigned each country a star and planet to be named. HD 117618 was assigned to [[Indonesia]]. The winning proposal named the star "Dofida" meaning ''our star'' in [[Nias language]], and its planet "Noifasui" meaning ''revolve around'' in Nias language (derived from the word ''ifasui'', meaning ''to revolve around'', and ''no'', indicating that the action occurred in the past and continued to the present time).<ref name="IAU Approved"/>

==Planetary system==

In 2005, the [[Anglo-Australian Planet Search]] program announced the discovery of a low-mass planet in orbit around HD 117618. This object was found through measurements of radial velocity variation, which were larger than those produced by the intrinsic jitter of the host star. The best [[Keplerian orbit|Keplerian]] fit to the data gave a [[orbital period|periodicity]] of 25.8 days with an [[orbital eccentricity|eccentricity]] of around 0.37 and a [[semimajor axis]] of {{Val|0.17|ul=AU}}. The [[lower bound]] on the object's mass was estimated to be {{val|0.16|ul=Jupiter mass}}.<ref name=Tinney2005/> These values were subsequently refined, as shown in the table below.<ref name="Butler2006"/>

{{OrbitboxPlanet begin | table_ref = <ref name="Butler2006"/> }} {{OrbitboxPlanet | exoplanet = [[HD 117618 b|b / Noifasui]] | mass = >0.178 ± 0.021 | period = {{Val|25.827|0.019}} | semimajor = 0.176 ± 0.010 | eccentricity = 0.42 ± 0.17 }} {{Orbitbox end}}

== See also == * [[HD 117207]] * [[List of extrasolar planets]]

==References== <references> <ref name=SIMBAD>{{cite simbad | title=HD 114837 | access-date=2018-07-05 }}</ref>

<ref name="IAU Approved">{{cite web | url=https://www.thejakartapost.com/news/2019/12/19/written-in-the-stars-native-nias-names-dofida-noifasui-chosen-for-planetary-system.html | title=Approved names (§ Indonesia) | website=Name Exo Worlds | publisher=[[IAU]] | access-date=18 January 2020 }}</ref>

<ref name=Raghavan2006>{{citation | title=Two Suns in The Sky: Stellar Multiplicity in Exoplanet Systems | display-authors=1 | last1=Raghavan | first1=Deepak | last2=Henry | first2=Todd J. | last3=Mason | first3=Brian D. | last4=Subasavage | first4=John P. | last5=Jao | first5=Wei-Chun | last6=Beaulieu | first6=Thom D. | last7=Hambly | first7=Nigel C. | journal=The Astrophysical Journal | postscript=. | volume=646 | issue=1 | pages=523–542 | date=July 2006 | doi=10.1086/504823 | bibcode=2006ApJ...646..523R | arxiv=astro-ph/0603836 | s2cid=5669768 }}</ref>

<ref name=Gray2006>{{cite journal | display-authors=1 | last1=Gray | first1=R. O. | last2=Corbally | first2=C. J. | last3=Garrison | first3=R. F. | last4=McFadden | first4=M. T. | last5=Bubar | first5=E. J. | last6=McGahee | first6=C. E. | last7=O'Donoghue | first7=A. A. | last8=Knox | first8=E. R. | title=Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample | journal=[[The Astronomical Journal]] | arxiv=astro-ph/0603770 | volume=132 | issue=1 | pages=161–170 | date=July 2006 | doi=10.1086/504637 | bibcode=2006AJ....132..161G | s2cid=119476992 }}</ref>

<ref name="Butler2006">{{cite journal | title=Catalog of Nearby Exoplanets | last1=Butler | first1=R. P. | last2=Wright | first2=J. T. | last3=Marcy | first3=G. W. | last4=Fischer | first4=D. A. | last5=Vogt | first5=S. S. | last6=Tinney | first6=C. G. | last7=Jones | first7=H. R. A. | last8=Carter | first8=B. D. | last9=Johnson | first9=J. A. | display-authors=1 | journal=The Astrophysical Journal | volume=646 | issue=1 | pages=505–522 | date=2006 | doi=10.1086/504701 | bibcode=2006ApJ...646..505B | arxiv=astro-ph/0607493 | hdl=2299/1103 | s2cid=119067572 }}</ref>

<ref name=Tinney2005>{{cite journal | title=Three Low-Mass Planets from the Anglo-Australian Planet Search | journal=The Astrophysical Journal | volume=623 | issue=2 | date=2005 | pages=1171–1179 | last1=Tinney | first1=C. G. | last2=Butler | first2=R. Paul | last3=Marcy | first3=Geoffrey W. | last4=Jones | first4=Hugh R. A. | last5=Penny | first5=Alan J. | last6=McCarthy | first6=Chris | last7=Carter | first7=Brad D. | last8=Fischer | first8=Debra A. | display-authors=1 | doi=10.1086/428661 | bibcode=2005ApJ...623.1171T | citeseerx=10.1.1.491.2941 | s2cid=12515735 }}</ref>

<ref name=Bonfanti2016>{{cite journal | title=Age consistency between exoplanet hosts and field stars | last1=Bonfanti | first1=A. | last2=Ortolani | first2=S. | last3=Nascimbeni | first3=V. | journal=Astronomy & Astrophysics | year=2016 | volume=585 | pages=A5, 14 pp | arxiv=1511.01744 | bibcode=2016A&A...585A...5B | doi=10.1051/0004-6361/201527297 | s2cid=53971692 }}</ref>

<ref name=Adibekyan2016>{{cite journal | display-authors=1 | title=Abundance trend with condensation temperature for stars with different Galactic birth places | last1=Adibekyan | first1=V. | last2=Delgado-Mena | first2=E. | last3=Figueira | first3=P. | last4=Sousa | first4=S. G. | last5=Santos | first5=N. C. | last6=González Hernández | first6=J. I. | last7=Minchev | first7=I. | last8=Faria | first8=J. P. | last9=Israelian | first9=G. | last10=Harutyunyan | first10=G. | last11=Suárez-Andrés | first11=L. | last12=Hakobyan | first12=A. A. | journal=Astronomy & Astrophysics | arxiv=1606.04714 | volume=592 | id=A87 | pages=12 | date=August 2016 | doi=10.1051/0004-6361/201628883 | bibcode=2016A&A...592A..87A | s2cid=56256991 }}</ref>

<ref name=Delgado_Mena2015>{{cite journal | display-authors=1 | last1=Delgado Mena | first1=E. | last2=Bertrán de Lis | first2=S. | last3=Adibekyan | first3=V. Zh. | last4=Sousa | first4=S. G. | last5=Figueira | first5=P. | last6=Mortier | first6=A. | last7=González Hernández | first7=J. I. | last8=Tsantaki | first8=M. | last9=Israelian | first9=G. | last10=Santos | first10=N. C. | title=Li abundances in F stars: planets, rotation, and Galactic evolution | journal=Astronomy & Astrophysics | arxiv=1412.4618 | volume=576 | id=A69 | pages=24 | date=April 2015 | doi=10.1051/0004-6361/201425433 | bibcode=2015A&A...576A..69D | s2cid=56051637 }}</ref> </references>

[[Category:G-type main-sequence stars]] [[Category:Planetary systems with one confirmed planet]] [[Category:Centaurus]] [[Category:Durchmusterung objects|CD-46 08708]] [[Category:Henry Draper Catalogue objects|117618]] [[Category:Hipparcos objects|066047]] [[Category:Stars with proper names|Dofida]]