{{Short description|Star in the constellation Grus}} {{Starbox begin | name = HD 208487 / Itonda }} {{Starbox observe | epoch = J2000 | constell = Grus<ref name=Anderson_Francis_2012/> | ra = {{RA|21|57|19.84754}}<ref name=GaiaDR3/> | dec = {{DEC|−37|45|49.0480}}<ref name=GaiaDR3/> | appmag_v = 7.47<ref name=Anderson_Francis_2012/> }} {{Starbox character | type = main sequence<ref name=GaiaDR3/> | class = G1/3V<ref name=houk1979/> | b-v = 0.568{{±|0.009}}<ref name=Anderson_Francis_2012/> | variable = Stable<ref name="Tinney2005"/> }} {{Starbox astrometry | radial_v = 5.575{{±|0.0004}}<ref name=Soubiran_et_al_2018/> | prop_mo_ra = 101.032 | prop_mo_dec = −118.842 | pm_footnote = <ref name=GaiaDR3/> | parallax = 22.2688 | p_error = 0.0304 | parallax_footnote = <ref name=GaiaDR3/> | absmag_v = 4.26<ref name="Tinney2005"/> | absmag_bol = 4.06<ref name="Tinney2005"/> }} {{Starbox detail | source = <ref name=Rubenstein2025/> | mass = {{Val|1.15|0.04}} | radius = {{Val|1.16|0.02}} | luminosity = {{val|1.71|0.09}} | temperature = {{Val|6134|54|50|fmt=commas}} | gravity = 4.36{{±|0.03}}<ref name=Bonfanti_et_al_2016/> | metal_fe = {{Val|+0.09|0.04}} | rotation = 29 days | age_gyr = {{Val|1.95|1.41|1.11}} | rotational_velocity = 3.688<ref name=Bonfanti_et_al_2016/> }} {{Starbox catalog | names = {{odlist | name=Itonda | CD=−38° 14804 | HD=208487 | HIP=108375 | PPM=302029 | SAO=213432 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad = HD+208487 | NSTED = HD-208487 }} {{Starbox end}}

'''HD 208487''' is a star with an orbiting exoplanet in the constellation of Grus. Based on parallax measurements, it is located at a distance of 146.5&nbsp;light years from the Sun. The absolute magnitude of HD 208487 is 4.26,<ref name="Tinney2005"/> but at that distance the apparent visual magnitude is 7.47,<ref name=Anderson_Francis_2012/> which is too faint to be viewed with the naked eye. The system is drifting further away with a radial velocity of 5.6&nbsp;km/s.<ref name=Soubiran_et_al_2018/> It is a member of the thin disk population.<ref name=Costa_Silva_et_al_2020/>

The spectrum of HD 208487 presents as an ordinary G-type main-sequence star with a stellar classification of G1/3V.<ref name=houk1979/> It is a relatively young star, with age estimates of 1–2 billion years, and is spinning with a projected rotational velocity of 3.7&nbsp;km/s.<ref name=Costa_Silva_et_al_2020/><ref name=Bonfanti_et_al_2016/> The star has 16% greater mass and a 17% larger radius than the Sun.<ref name=Bonfanti_et_al_2016/> The abundance of iron, a measure of the star's metallicity, is similar to the Sun.<ref name=Costa_Silva_et_al_2020/> It is radiating 176% of the luminosity of the Sun from its photosphere at an effective temperature of 6,143&nbsp;K.<ref name=Bonfanti_et_al_2016/> The level of magnetic activity in the chromosphere is low.<ref name="Tinney2005"/>

The star HD 208487 is named '''Itonda''' and the exoplanet ''Mintome''. The names were selected in the NameExoWorlds campaign by Gabon, during the 100th anniversary of the IAU. Itonda, in the Myene tongue, corresponds to all that is beautiful. Mintome, in the Fang tongue, is a mythical land where a brotherhood of brave men live.<ref name=exoworlds/><ref name=iau/>

== Planetary system == There is one confirmed planet orbiting the star HD 208487, which is designated HD 208487 b.<ref name="Tinney2005"/> It has a mass at least half that of Jupiter and is located in an eccentric 130-day orbit.

The discovery of a second planet in the system was announced on 13 September 2005, by P.C. Gregory. The discovery was made using Bayesian analysis of the radial velocity dataset to determine the planetary parameters.<ref name=Gregory_2007/> However, further analysis revealed that an alternative two-planet solution for the HD 208487 system was possible, with a planet in a 28-day orbit instead of the 908-day orbit postulated, and it was concluded that activity on the star is more likely to be responsible for the residuals to the one-planet solution than the presence of a second planet.<ref name="Wright2007"/>

A 2025 study detected two radial velocity candidates at periods of 923 and 1,280 days, none of which is correlated to stellar activity signals. The former has a period close to the challenged planet. Planet c, with the shortest period, would have a minimum mass of {{jupiter mass|0.32}} and thus be similar to Saturn, while planet d would have a minimum mass of {{jupiter mass|0.15}} and thus be a super-Neptune.<ref name=Rubenstein2025/>

If both candidates are confirmed, the system of HD 208487 would challenge the "Peas in a Pod" trend{{snd}}when planetary systems with three or more planets are evenly spaced around the host star{{snd}} given that the orbits of c and d are close to each other, but distant from that of planet b. The bodies may have been initially equally-spaced, but due to mutual gravitational perturbations, migrated from their original orbits.<ref name=Rubenstein2025/> {{OrbitboxPlanet begin | table_ref = <ref name=Rubenstein2025/> }} {{OrbitboxPlanet | exoplanet = b / Mintome | mass = {{Val|0.46|0.01|0.00|p=≥}} | period = {{val|129.36|0.02}} | semimajor = {{Val|0.53|0.00}} | eccentricity = {{Val|0.37|0.01}} }} {{OrbitboxPlanet hypothetical | exoplanet = c | mass = {{Val|0.32|0.01|p=≥}} | period = {{Val|923.06|2.02|2.76}} | semimajor = {{Val|1.94|0.01}} | eccentricity = {{Val|0.19|0.01|0.02}} }} {{OrbitboxPlanet hypothetical | exoplanet = d | mass = {{Val|0.15|0.01|0.02|p=≥}} | period = {{Val|1380.13|19.20|8.25|fmt=commas}} | semimajor = {{Val|2.54|0.02|0.01}} | eccentricity = {{Val|0.11|0.03|0.06}} }} {{Orbitbox end}}

== See also == * Lists of exoplanets

== References == {{Reflist|refs=

<ref name=SIMBAD>{{cite simbad|title=HD 208487|accessdate=2020-05-06}}</ref>

<ref name=GaiaDR3>{{Cite Gaia DR3|6586580842340695040}}</ref>

<ref name=Anderson_Francis_2012>{{citation | 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 | doi=10.1134/S1063773712050015 | arxiv=1108.4971 | s2cid=119257644 | postscript=. }}</ref>

<ref name=Soubiran_et_al_2018>{{cite journal | title=Gaia Data Release 2. The catalogue of radial velocity standard stars | last1=Soubiran | first1=C. | last2=Jasniewicz | first2=G. | last3=Chemin | first3=L. | last4=Zurbach | first4=C. | last5=Brouillet | first5=N. | last6=Panuzzo | first6=P. | last7=Sartoretti | first7=P. | last8=Katz | first8=D. | last9=Le Campion | first9=J. -F. | last10=Marchal | first10=O. | last11=Hestroffer | first11=D. | last12=Thévenin | first12=F. | last13=Crifo | first13=F. | last14=Udry | first14=S. | last15=Cropper | first15=M. | last16=Seabroke | first16=G. | last17=Viala | first17=Y. | last18=Benson | first18=K. | last19=Blomme | first19=R. | last20=Jean-Antoine | first20=A. | last21=Huckle | first21=H. | last22=Smith | first22=M. | last23=Baker | first23=S. G. | last24=Damerdji | first24=Y. | last25=Dolding | first25=C. | last26=Frémat | first26=Y. | last27=Gosset | first27=E. | last28=Guerrier | first28=A. | last29=Guy | first29=L. P. | last30=Haigron | first30=R. | display-authors=1 | journal=Astronomy and Astrophysics | volume=616 | pages=A7 | year=2018 | bibcode=2018A&A...616A...7S | arxiv=1804.09370 | doi=10.1051/0004-6361/201832795 | s2cid=52952408 }}</ref>

<ref name=houk1979>{{cite book | title=Michigan catalogue of two-dimensional spectral types for the HD stars | last1=Houk | first1=Nancy | location=Ann Arbor, Michigan | publisher=Dept. of Astronomy, University of Michigan | volume=3 | date=1982 | bibcode=1982mcts.book.....H }}</ref>

<ref name=Bonfanti_et_al_2016>{{cite journal | title=Age consistency between exoplanet hosts and field stars | display-authors=1 | last1=Bonfanti | first1=A. | last2=Ortolani | first2=S. | last3=Nascimbeni | first3=V. | journal=Astronomy & Astrophysics | year=2016 | volume=585 | id=A5 | pages=14 | arxiv=1511.01744 | bibcode=2016A&A...585A...5B | doi=10.1051/0004-6361/201527297 | s2cid=53971692 }}</ref>

<ref name="Tinney2005">{{cite journal | title=Three Low-Mass Planets from the Anglo-Australian Planet Search | 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 | journal=The Astrophysical Journal | volume=623 | issue=2 | date=2005 | pages=1171–1179 | bibcode=2005ApJ...623.1171T | doi=10.1086/428661 | citeseerx=10.1.1.491.2941 | s2cid=12515735 }}</ref>

<ref name=Gregory_2007>{{cite journal | title=A Bayesian Kepler periodogram detects a second planet in HD 208487 | last=Gregory | first=P.C. | journal=Monthly Notices of the Royal Astronomical Society | year=2007 | volume=374 | issue=4 | pages=1321–1333 | doi=10.1111/j.1365-2966.2006.11240.x | doi-access=free | s2cid=8220838 | bibcode=2007MNRAS.374.1321G | arxiv=astro-ph/0609229 }}</ref>

<ref name="Wright2007">{{cite journal | title=Four New Exoplanets and Hints of Additional Substellar Companions to Exoplanet Host Stars | display-authors=1 | last1=Wright | first1=J.T. | last2=Marcy | first2=G. W. | last3=Fischer | first3=D. A. | last4=Butler | first4=R. P. | 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. | last10=McCarthy | first10=C. | last11=Apps | first11=K. | journal=The Astrophysical Journal | volume=657 | issue=1 | pages=533–545 | date=2007 | doi=10.1086/510553 | bibcode=2007ApJ...657..533W | arxiv=astro-ph/0611658 | s2cid=35682784 }}</ref>

<ref name=Costa_Silva_et_al_2020>{{cite journal | title=Chemical abundances of 1111 FGK stars from the HARPS-GTO planet search sample. III. Sulfur | display-authors=1 | last1=Costa Silva | first1=A. R. | last2=Delgado Mena | first2=E. | last3=Tsantaki | first3=M. | journal=Astronomy & Astrophysics | volume=634 | id=A136 | pages=10 | date=February 2020 | doi=10.1051/0004-6361/201936523 | arxiv=1912.08659 | bibcode=2020A&A...634A.136C | s2cid=209405391 }}</ref>

<ref name=Rubenstein2025>{{Cite arXiv |last1=Rubenstein |first1=Rafael I. |last2=Jenkins |first2=James S. |last3=R |first3=Pablo A. Peña |last4=Charalambous |first4=Carolina |last5=Tuomi |first5=Mikko |last6=Alves |first6=Douglas R. |last7=Vines |first7=José |last8=Díaz |first8=Matías R. |last9=Saha |first9=Suman |title=Destruction of "Peas in a Pod?" A Candidate Multi-planet System Around the Nearby, Bright Star, HD208487 |date=2025-08-17 |eprint=2508.12447 |class=astro-ph.EP}}</ref>

<ref name=exoworlds>{{Cite web | title=Approved names|website=NameExoworlds | url=http://www.nameexoworlds.iau.org/final-results | language=en | access-date=2020-01-02 }}</ref>

<ref name=iau>{{Cite web | title=International Astronomical Union {{!}} IAU | url=https://www.iau.org/news/pressreleases/detail/iau1912/ | website=www.iau.org | access-date=2020-01-02 | archive-date=2022-12-05 | archive-url=https://web.archive.org/web/20221205123842/http://www.iau.org/news/pressreleases/detail/iau1912/ | url-status=dead }}</ref>

}}

== External links == * {{cite encyclopedia | encyclopedia=Extrasolar Planets Encyclopaedia | title=Notes for star HD 208487 | access-date=2008-08-29 | url=http://exoplanet.eu/star.php?st=HD+208487 | archive-url=https://web.archive.org/web/20060620235248/http://exoplanet.eu/star.php?st=HD+208487 | url-status=dead | archive-date=June 20, 2006 }}

{{Stars of Grus}}{{Sky|21|57|19.8477|-|37|45|49.037|144.4}} {{Authority control}}

<!-- Properties --> Category:G-type main-sequence stars Category:Planetary systems with one confirmed planet <!-- Location/catalogues --> Category:Grus (constellation) CD-38 14804 208487 108375 Itonda