HIP 70849

{{Short description|Star in the constellation Lupus}} {{Starbox begin}} {{Starbox observe | epoch = J2000.0 | constell = [[Lupus (constellation)|Lupus]] | ra = {{RA|14|29|18.56436}}<ref name=GaiaDR3/> | dec = {{DEC|−46|27|49.7378}}<ref name=GaiaDR3/> | appmag_v = 10.36<ref name=Anderson_Francis_2012/> }} {{Starbox character | type = | class = K7Vk<ref name=Gray_et_al_2006/> | appmag_1_passband = B | appmag_1 = 11.787<ref name=Anderson_Francis_2012/> | appmag_2_passband = J | appmag_2 = 7.639{{±|0.023}}<ref name=Anderson_Francis_2012/> | appmag_3_passband = H | appmag_3 = 7.006{{±|0.061}}<ref name=Anderson_Francis_2012/> | appmag_4_passband = K | appmag_4 = 6.790{{±|0.027}}<ref name=Anderson_Francis_2012/> | r-i = | v-r = | b-v = 1.427{{±|0.019}}<ref name=Anderson_Francis_2012/> | u-b = | variable = 8.50<ref name=Anderson_Francis_2012/> }} {{Starbox astrometry | radial_v = {{val|−0.134|0.0013}}<ref name=Soubiran_et_al_2018/> | prop_mo_ra = {{val|−44.051|0.017}} | prop_mo_dec = {{val|−201.577|0.020}} | pm_footnote = <ref name=GaiaDR3/> | parallax = 41.4618 | p_error = 0.0175 | parallax_footnote = <ref name=GaiaDR3/> | absmag_v = 8.5<ref name=Anderson_Francis_2012/> }} {{Starbox detail | source = | mass = {{Val|0.647|0.013}}<ref name=An2025/> | radius = 0.62{{±|0.02}}<ref name=Zurlo_et_al_2018/> | gravity = 3.70{{±|0.09}}<ref name=Sousa_et_al_2018/> | luminosity_bolometric = 0.0892{{±|0.0005}}<ref name=Zurlo_et_al_2018/> | temperature = {{val|4103|25|fmt=commas}}<ref name=Sousa_et_al_2018/> | metal_fe = 0.00{{±|0.03}}<ref name=Sousa_et_al_2018/> | age_gyr = 3.6{{±|0.15}}<ref name=Zurlo_et_al_2018/> | rotation = {{val|41.2|u=days}}<ref name=Zurlo_et_al_2018/> | rotational_velocity = {{val|1.93|u=km/s}}<ref name=Zurlo_et_al_2018/><br/>0.30{{±|0.30}}<ref name=Sousa_et_al_2018/> }} {{Starbox catalog | names = {{odlist | CD=−45°9206 | GJ=550.3 | HIP=70849 | LTT=5717 | NLTT=37446 | NSV=6678 | PPM=760399 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad = HIP+70849 | NSTED = HIP 70849 | EPE = HIP+70849 }} {{Starbox end}}

'''HIP 70849''' is a [[star]] with two non-stellar companions in the southern [[constellation]] [[Lupus (constellation)|Lupus]]. It is a 10th [[apparent magnitude|magnitude]] star, making it too faint to be visible to the naked eye.<ref name=Anderson_Francis_2012/> The system is located at a distance of 78.7 [[light-year]]s from the [[Sun]] based on [[stellar parallax|parallax]] measurements.<ref name=GaiaDR3/>

This is a [[K-type main-sequence star]] with a [[stellar classification]] of K7Vk,<ref name=Gray_et_al_2006/> where the 'k' indicates interstellar absorption features in the [[stellar spectrum|spectrum]]. The star is [[magnetic activity|magnetically active]] with a {{val|10.1|1.4|u=yr}} starspot cycle. It appears about 3.6 billion years old and the light emission shows a 41.2 day periodicity, which is likely the [[rotation period]].<ref name=Zurlo_et_al_2018/> This star, which resembles a brighter [[red dwarf]], is smaller and less massive than the Sun. It is radiating just 9%<ref name=Zurlo_et_al_2018/> of the luminosity of the Sun from its [[photosphere]] at an [[effective temperature]] of 4,103 K.<ref name=Sousa_et_al_2018/>

The companion is a T4.5 [[brown dwarf]] companion orbiting it at a separation around ~9,000 [[astronomical unit|AU]].<ref name="Lodieu2014"/><ref name="Šubjak2022"/>

==Planetary system== In 2009, a [[gas giant]] planet was found in orbit around it.<ref name="Ségransan2011"/> Designated HIP 70849 b, it has 4.55 times the mass of [[Jupiter]] and takes 10.05 years to orbit at a [[semimajor axis]] of {{val|4.04|ul=AU}}, with a high eccentricity.<ref name=An2025/>

{{OrbitboxPlanet begin | table_ref = <ref name=An2025/> | period_unit = year }} {{OrbitboxPlanet | exoplanet = [[HIP 70849 b|b]] | mass = {{val|4.55|0.51}} | period = {{val|10.046|0.054|0.046}} | semimajor = {{val|4.037|0.030}} | eccentricity = {{val|0.584|0.070|0.079}} | inclination = {{val|130|14|26}} }} {{Orbitbox end}}

== References == {{Reflist|refs=

<ref name=SIMBAD>{{cite simbad | title=CD-45 9206 | access-date=2021-11-11 }}</ref>

<ref name=Anderson_Francis_2012>{{cite journal | last1=Anderson | first1=E. | last2=Francis | first2=Ch. | title=XHIP: An extended hipparcos compilation | journal=Astronomy Letters | volume=38 | issue=5 | pages=331 | year=2012 | bibcode=2012AstL...38..331A | arxiv=1108.4971 | doi=10.1134/S1063773712050015 | s2cid=119257644 }}</ref>

<ref name=An2025>{{cite journal |last=An |first=Qier |last2=Brandt |first2=Timothy D. |last3=Brandt |first3=G. Mirek |last4=Venner |first4=Alexander |title=Orbits and Masses for 156 Companions from Combined Astrometry and Radial Velocities, and A Validation of Gaia Non-Single Star Solutions |date=2025-08-11 |journal=[[The Astrophysical Journal Supplement Series]] |arxiv=2508.08374}}</ref>

<ref name="Ségransan2011">{{cite journal | title=The HARPS search for southern extra-solar planets. XXIX. Four new planets in orbit around the moderately active dwarfs HD 63765, HD 104067, HD 125595, and HIP 70849 | last1=Ségransan | first1=D. | last2=Mayor | first2=M. | last3=Udry | first3=S. | last4=Lovis | first4=C. | last5=Benz | first5=W. | last6=Bouchy | first6=F. | last7=Lo Curto | first7=G. | last8=Mordasini | first8=C. | last9=Moutou | first9=C. | last10=Naef | first10=D. | last11=Pepe | first11=F. | last12=Queloz | first12=D. | last13=Santos | first13=N. | display-authors=1 | journal=Astronomy and Astrophysics | volume=535 | at=A54 | year=2011 | arxiv=1107.0339 | bibcode=2011A&A...535A..54S | doi=10.1051/0004-6361/200913580 | s2cid=119197766 }}</ref>

<ref name="Lodieu2014">{{cite journal | title=Binary frequency of planet-host stars at wide separations. A new brown dwarf companion to a planet-host star | last1=Lodieu | first1=N. | last2=Pérez-Garrido | first2=A. | last3=Béjar | first3=V. J. S. | last4=Gauza | first4=B. | last5=Ruiz | first5=M. T. | last6=Rebolo | first6=R. | last7=Pinfield | first7=D. J. | last8=Martín | first8=E. L. | display-authors=1 | journal=Astronomy and Astrophysics | volume=569 | at=A120 | year=2014 | arxiv=1408.1208 | bibcode=2014A&A...569A.120L | doi=10.1051/0004-6361/201424210 | s2cid=118516214 }}</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=Gray_et_al_2006>{{cite journal | 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 | display-authors=1 | journal=[[The Astronomical Journal]] | volume=132 | issue=1 | pages=161–170 | date=July 2006 | doi=10.1086/504637 | bibcode=2006AJ....132..161G | arxiv=astro-ph/0603770 | s2cid=119476992 }}</ref>

<ref name=Zurlo_et_al_2018>{{cite journal | title=Imaging radial velocity planets with SPHERE | last1=Zurlo | first1=A. | last2=Mesa | first2=D. | last3=Desidera | first3=S. | last4=Messina | first4=S. | last5=Gratton | first5=R. | last6=Moutou | first6=C. | last7=Beuzit | first7=J. -L. | last8=Biller | first8=B. | last9=Boccaletti | first9=A. | last10=Bonavita | first10=M. | last11=Bonnefoy | first11=M. | last12=Bhowmik | first12=T. | last13=Brandner | first13=W. | last14=Buenzli | first14=E. | last15=Chauvin | first15=G. | last16=Cudel | first16=M. | last17=D'Orazi | first17=V. | last18=Feldt | first18=M. | last19=Hagelberg | first19=J. | last20=Janson | first20=M. | last21=Lagrange | first21=A. -M. | last22=Langlois | first22=M. | last23=Lannier | first23=J. | last24=Lavie | first24=B. | last25=Lazzoni | first25=C. | last26=Maire | first26=A. -L. | last27=Meyer | first27=M. | last28=Mouillet | first28=D. | last29=Peretti | first29=S. | last30=Perrot | first30=C. | last31=Potiron | first31=P. J. | last32=Salter | first32=G. | last33=Schmidt | first33=T. | last34=Sissa | first34=E. | last35=Vigan | first35=A. | last36=Delboulbé | first36=A. | last37=Petit | first37=C. | last38=Ramos | first38=J. | last39=Rigal | first39=F. | last40=Rochat | first40=S. | display-authors=1 | journal=Monthly Notices of the Royal Astronomical Society | volume=480 | issue=1 | pages=35–48 | date=October 2018 | doi=10.1093/mnras/sty1809 | doi-access=free | arxiv=1807.01324 | bibcode=2018MNRAS.480...35Z }}</ref>

<ref name=Sousa_et_al_2018>{{cite journal | title=SWEET-Cat updated. New homogenous spectroscopic parameters | display-authors=1 | last1=Sousa | first1=S. G. | last2=Adibekyan | first2=V. | last3=Delgado-Mena | first3=E. | last4=Santos | first4=N. C. | last5=Andreasen | first5=D. T. | last6=Ferreira | first6=A. C. S. | last7=Tsantaki | first7=M. | last8=Barros | first8=S. C. C. | last9=Demangeon | first9=O. | last10=Israelian | first10=G. | last11=Faria | first11=J. P. | last12=Figueira | first12=P. | last13=Mortier | first13=A. | last14=Brandão | first14=I. | last15=Montalto | first15=M. | last16=Rojas-Ayala | first16=B. | last17=Santerne | first17=A. | journal=Astronomy & Astrophysics | volume=620 | id=A58 | pages=13 | date=November 2018 | doi=10.1051/0004-6361/201833350 | arxiv=1810.08108 | bibcode=2018A&A...620A..58S | s2cid=119374557 }}</ref>

<ref name="Šubjak2022">{{cite journal |last1=Šubjak |first1=J. |last2=Lodieu |first2=N. |display-authors=etal |title=Search for planets around stars with wide brown dwarfs |journal=[[Astronomy & Astrophysics]] |year=2023 |volume= 671|issue= |pages= A10|doi= 10.1051/0004-6361/202244238|arxiv=2212.03757|bibcode=2023A&A...671A..10S |s2cid=254366726 }}</ref>

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[[Category:K-type main-sequence stars]] [[Category:Planetary systems with one confirmed planet]] [[Category:Lupus (constellation)]] [[Category:Durchmusterung objects]] [[Category:Gliese and GJ objects|0550.3]] [[Category:Hipparcos objects|070849]] [[Category:T-type brown dwarfs]]