{{Short description|Star in the constellation Draco}} {{Starbox begin}} {{Starbox image | image = {{Location mark |image=Draco constellation map.svg|alt=|float=center|width=280 |label=|position=right |mark=Red circle.svg|mark_width=10|mark_link=HD 167042 |x=175|y=882 }} | caption = Location of HD 167042 (circled in red) }} {{Starbox observe | epoch = [[J2000.0]] | equinox = [[J2000.0]] ([[International Celestial Reference System|ICRS]]) | constell = [[Draco (constellation)|Draco]]<ref name=constellation/> | ra = {{RA|18|10|31.640}}<ref name=GaiaDR3/> | dec = {{DEC|+54|17|11.59}}<ref name=GaiaDR3/> | appmag_v = +5.97<ref name=Ligi2016/> }} {{Starbox character | type = [[red giant branch]]<ref name=white2018/><ref name=GaiaDR3/> | class = K1 III<ref name=Sharma_et_al_2020/> or K1 IV<ref name=Ligi2016/> | b-v = +0.934<ref name=mnras172_667/> | u-b = +0.716<ref name=mnras172_667/> | variable = }} {{Starbox astrometry | radial_v = −17.88<ref name=Jofre2015/> | prop_mo_ra = +107.630 | prop_mo_dec = +247.345 | pm_footnote = <ref name=GaiaDR3/> | parallax = 20.1313 | p_error = 0.0293 | parallax_footnote = <ref name=GaiaDR3/> | absmag_v = 2.48<ref name="Johnson2008"/> }} {{Starbox detail | source = <ref name=Lin2025/> | mass = {{val|1.4696|0.0532}} | radius = {{val|4.4947|0.0576}} | luminosity = {{val|10.717|0.924|0.850}} | temperature = {{val|4926|79|fmt=commas}} | gravity = {{val|3.3008|0.0050}} | metal_fe = +{{val|0.093|0.061}} | rotational_velocity = 0.68<ref name=Jofre2015/> | age_gyr = {{val|7.413|0.829}} }} {{Starbox catalog | names = {{odlist | BD=+54°1950 | GC=24820 | HD=167042 | HIP=89017 | HR=6817 | LTT=15382 | PPM=36415 | SAO=30784 | Wolf=1415 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad = HD+167042 | NSTED = HD-167042 }} {{Starbox end}}
'''HD 167042''' is a [[star]] with an orbiting [[exoplanet]] in the northern [[constellation]] of [[Draco (constellation)|Draco]]. With an [[apparent visual magnitude]] of +5.97,<ref name=Ligi2016/> the star is dimly visible to the naked eye. It is located at a distance of 162 [[light year]]s based on [[stellar parallax|parallax]] measurements,<ref name=GaiaDR3/> but it is drifting closer with a [[radial velocity]] of −18 km/s.<ref name=Jofre2015/> HD 167042 has a relatively large [[proper motion]], traversing the [[celestial sphere]] at an [[angular rate]] of {{val|0.270|u=arcsecond}} yr<sup>−1</sup>.<ref name=Lepine_Shara_2005/>
The [[stellar spectrum|spectrum]] of HD 167042 presents as an [[stellar evolution|evolved]] [[K-type star|K-type]] [[giant star]], an orange giant, with a [[stellar classification]] of K1 III.<ref name=Sharma_et_al_2020/> The position of this star on the [[H-R diagram]] is at the base of the [[red giant branch]].<ref name=white2018/> When this star was a [[main sequence]], it was white-hued mid to late [[A-type star]] based on its mass. It shows no significant [[magnetic activity]] in its [[chromosphere]].<ref name="Johnson2008"/> The star has 1.88 times the mass of the Sun and has expanded to 4.49 times the Sun's radius. It is radiating 10.7 times the luminosity of the Sun from its [[photosphere]] at an [[effective temperature]] of 4,926 K.<ref name=Lin2025/>
== Planetary system == On 28 November 2007, a [[preprint]] of the discovery of the exoplanet [[HD 167042 b]] was posted to the [[arXiv]] server. The [[peer review]]ed paper was then published in The [[Astrophysical Journal]] on 1 March 2008.<ref name="Johnson2008"/> The discovery was later independently confirmed.<ref name="Sato2008"/> There is a long-period [[radial velocity]] trend, which might indicate the presence of a second substellar companion.<ref name=Teng2023/>
{{OrbitboxPlanet begin | table_ref = <ref name=Teng2023/> }} {{OrbitboxPlanet | exoplanet = [[HD 167042 b|b]] | mass = {{val|1.397|0.031|0.044|p=≥}} | period = {{val|417.67|0.43|0.41}} | semimajor = {{val|1.220|0.001}} | eccentricity = {{val|0.010|0.033|0.004}} }} {{Orbitbox end}}
== See also == * [[HD 16175]] * [[Kappa Coronae Borealis]] * [[List of extrasolar planets]]
== References == {{Reflist|refs=
<ref name=SIMBAD>{{cite simbad | title=HD 167042 | access-date=2017-08-12 }}</ref>
<ref name=GaiaDR3>{{Cite Gaia DR3|2149564787289902848}}</ref>
<ref name=constellation>{{cite constellation|HD 167042}}</ref>
<ref name=mnras172_667>{{cite journal | last1=Jennens | first1=P. A. | last2=Helfer | first2=H. L. | title=A new photometric metal abundance and luminosity calibration for field G and K giants | journal=[[Monthly Notices of the Royal Astronomical Society]] | volume=172 | issue=3 | pages=667–679 | date=September 1975 | bibcode=1975MNRAS.172..667J | doi=10.1093/mnras/172.3.667 | doi-access=free }}</ref>
<ref name=Jofre2015>{{cite journal | title=Stellar parameters and chemical abundances of 223 evolved stars with and without planets | last1=Jofré | first1=E. | last2=Petrucci | first2=R. | last3=Saffe | first3=C. | last4=Saker | first4=L. | last5=Artur de la Villarmois | first5=E. | last6=Chavero | first6=C. | last7=Gómez | first7=M. | last8=Mauas | first8=P. J. D. | s2cid=53666931 | journal=Astronomy & Astrophysics | display-authors=1 | volume=574 | pages=A50 | year=2015 | arxiv=1410.6422 | bibcode=2015A&A...574A..50J | doi=10.1051/0004-6361/201424474 }}</ref>
<ref name=Ligi2016>{{cite journal | title=Radii, masses, and ages of 18 bright stars using interferometry and new estimations of exoplanetary parameters | last1=Ligi | first1=R. | last2=Creevey | first2=O. | last3=Mourard | first3=D. | last4=Crida | first4=A. | last5=Lagrange | first5=A.-M. | last6=Nardetto | first6=N. | last7=Perraut | first7=K. | last8=Schultheis | first8=M. | last9=Tallon-Bosc | first9=I. | last10=ten Brummelaar | first10=T. | journal=Astronomy & Astrophysics | display-authors=1 | volume=586 | id=A94 | pages=23 | date=February 2016 | doi=10.1051/0004-6361/201527054 | bibcode=2016A&A...586A..94L |arxiv = 1511.03197 | s2cid=15941645 }}</ref>
<ref name="Johnson2008">{{cite journal | title=Retired A Stars and Their Companions. II. Jovian Planets Orbiting κ CrB and HD 167042 | last1=Johnson | first1=John Asher | last2=Marcy | first2=Geoffrey W. | last3=Fischer | first3=Debra A. | last4=Wright | first4=Jason T. | last5=Reffert | first5=Sabine | last6=Kregenow | first6=Julia M. | last7=Williams | first7=Peter K. G. | last8=Peek | first8=Kathryn M. G. | display-authors=1 | journal=The Astrophysical Journal | date=2008 | volume=675 | issue=1 | pages=784–789 | arxiv=0711.4367 | bibcode=2008ApJ...675..784J | doi=10.1086/526453 | s2cid=12367629 }}</ref>
<ref name=Lin2025>{{Cite journal |last1=Lin |first1=Wen-Xu |last2=Qian |first2=Sheng-Bang |last3=Zhu |first3=Li-Ying |last4=Liao |first4=Wen-Ping |last5=Li |first5=Fu-Xing |last6=Shi |first6=Xiang-Dong |last7=Li |first7=Lin-Jia |last8=Zhao |first8=Er-Gang |date=February 2025 |title=Comprehensive Parameter Determination of Exoplanets through Asteroseismic Host Star Constraints |journal=The Astrophysical Journal |language=en |volume=980 |issue=2 |pages=174 |doi=10.3847/1538-4357/ada60b |doi-access=free |arxiv=2502.18769 |bibcode=2025ApJ...980..174L |issn=0004-637X}}</ref>
<ref name="Sato2008">{{cite journal | title=Planetary Companions to Evolved Intermediate-Mass Stars: 14 Andromedae, 81 Ceti, 6 Lyncis, and HD167042 | last1=Sato | first1=Bun'ei | last2=Toyota | first2=Eri | last3=Omiya | first3=Masashi | last4=Izumiura | first4=Hideyuki | last5=Kambe | first5=Eiji | last6=Masuda | first6=Seiji | last7=Takeda | first7=Yoichi | last8=Itoh | first8=Yoichi | last9=Ando | first9=Hiroyasu | last10=Yoshida | first10=Michitoshi | last11=Kokubo | first11=Eiichiro | last12=Ida | first12=Shigeru | display-authors=1 | journal=Publications of the Astronomical Society of Japan | volume=60 | issue=6 | pages=1317–1326 | date=2008 | arxiv=0807.0268 | bibcode=2008PASJ...60.1317S | doi=10.1093/pasj/60.6.1317| s2cid=67841762 }}</ref>
<ref name=Lepine_Shara_2005>{{cite journal | last1=Lépine | first1=Sébastien | last2=Shara | first2=Michael M. | title=A Catalog of Northern Stars with Annual Proper Motions Larger than 0.15" (LSPM-NORTH Catalog) | journal=The Astronomical Journal | volume=129 | issue=3 | pages=1483–1522 | date=March 2005 | doi=10.1086/427854 | bibcode=2005AJ....129.1483L | arxiv=astro-ph/0412070 | s2cid=2603568 }}</ref>
<ref name=Sharma_et_al_2020>{{cite journal | title=Application of convolutional neural networks for stellar spectral classification | last1=Sharma | first1=Kaushal | last2=Kembhavi | first2=Ajit | last3=Kembhavi | first3=Aniruddha | last4=Sivarani | first4=T. | last5=Abraham | first5=Sheelu | last6=Vaghmare | first6=Kaustubh | display-authors=1 | journal=Monthly Notices of the Royal Astronomical Society | volume=491 | issue=2 | pages=2280–2300 | date=January 2020 | doi=10.1093/mnras/stz3100 | doi-access=free | arxiv=1909.05459 | bibcode=2020MNRAS.491.2280S }}</ref>
<ref name=Teng2023>{{cite journal |last1=Teng |first1=Huan-Yu |last2=Sato |first2=Bun'ei |display-authors=etal |date=December 2023 |title=Revisiting planetary systems in the Okayama Planet Search Program: A new long-period planet, RV astrometry joint analysis, and a multiplicity-metallicity trend around evolved stars |journal=[[Publications of the Astronomical Society of Japan]] |volume=75 |issue=6 |pages=1030–1071 |doi=10.1093/pasj/psad056 |arxiv=2308.05343 |bibcode=2023PASJ...75.1030T}}</ref>
<ref name=white2018>{{cite journal | title=Interferometric diameters of five evolved intermediate-mass planet-hosting stars measured with PAVO at the CHARA Array | display-authors=1 | last1=White | first1=T. R. | last2=Huber | first2=D. | last3=Mann | first3=A. W. | last4=Casagrande | first4=L. | last5=Grunblatt | first5=S. K. | last6=Justesen | first6=A. B. | last7=Silva Aguirre | first7=V. | last8=Bedding | first8=T. R. | last9=Ireland | first9=M. J. | last10=Schaefer | first10=G. H. | last11=Tuthill | first11=P. G. | journal=Monthly Notices of the Royal Astronomical Society | volume=477 | issue=4 | pages= 4403–4413 | date=July 2018 | doi=10.1093/mnras/sty898 | doi-access=free | arxiv=1804.05976 | bibcode=2018MNRAS.477.4403W | s2cid=48365395 }}</ref>
}}
== External links == * {{cite encyclopedia | title=Notes for star HD 167042 | encyclopedia=[[Extrasolar Planets Encyclopaedia]] | url=http://exoplanet.eu/star.php?st=HD+167042 | archive-url=https://web.archive.org/web/20071106054820/http://exoplanet.eu/star.php?st=HD+167042 | url-status=dead | archive-date=November 6, 2007 | access-date=2008-08-24 }} {{Stars of Draco}} {{Sky|18|10|31.6403|+|54|17|11.588|163}}
<!-- Properties --> [[Category:K-type giants]] [[Category:Planetary systems with one confirmed planet]] <!-- Location/catalogues --> [[Category:Draco (constellation)]] [[Category:Bright Star Catalogue objects|6817]] [[Category:Durchmusterung objects|BD+54 1950]] [[Category:Henry Draper Catalogue objects|167042]] [[Category:Hipparcos objects|089017]]