{{Short description|Red dwarf in constellation of Draco}} {{Starbox begin}} {{Starbox observe | epoch = J2000 | constell = [[Draco (constellation)|Draco]] | ra = {{RA|16|25|24.62304}}<ref name="GaiaDR3"/> | dec = {{DEC|+54|18|14.7655}}<ref name="GaiaDR3"/> | appmag_v = 10.13<ref name=Anderson_Francis_2012/> }} {{Starbox character | type = | class = M1.5V<ref name=Alonso-Floriano_et_al_2015/> | b-v = 1.591{{±|0.027}}<ref name=Anderson_Francis_2012/> | v-i = 2.58{{±|0.06}}<ref name=Anderson_Francis_2012/> | u-b = | variable = }} {{Starbox astrometry | radial_v = {{val|−13.37|0.14}}<ref name="GaiaDR3"/> | prop_mo_ra = {{val|432.230|(19)}} | prop_mo_dec = {{val|−171.652|(22)}} | pm_footnote = <ref name="GaiaDR3"/> | parallax = 154.3503 | p_error = 0.0161 | parallax_footnote = <ref name="GaiaDR3"/> | absmag_v = 11.06<ref name=Anderson_Francis_2012/> }} {{Starbox detail | mass = 0.240{{±|0.013}}<ref name=Khata_et_al_2020/> | radius = 0.255{{±|0.034}}<ref name=Khata_et_al_2020/> | temperature = {{val|3557|9|fmt=commas}}<ref name=Fouqué_et_al_2018/> | luminosity = 0.01482{{±|0.00022}}<ref name="SchweitzerPassegger2019"/> | gravity = 4.94{{±|0.06}}<ref name="Suárez Mascareño2017"/> | metal_fe = −0.401{{±|0.005}}<ref name=Fouqué_et_al_2018/> | age_gyr = | rotation = {{val|77.8|5.5|u=days}}<ref name="Suárez Mascareño2017"/> | rotational_velocity = 2.2{{±|0.7}}<ref name=Fouqué_et_al_2018/> }} {{Starbox catalog | names = {{odlist | G=202-48 | G2=226-7 | G3=225-62 | AC=+54 1646 | GJ=625 | NLTT=42804 | PLX=3740.03 | HIP=80459 | TYC=3878-1193-1 | LSPM=J1625+5418 | 2MASS=J16252459+5418148 }}<ref name=SIMBAD/> }} {{Starbox reference | Simbad = GJ+625 | NSTED = GJ-625 }} {{Starbox end}}
'''GJ 625''' ('''AC 54 1646-56''') is a small [[red dwarf]] star with an [[exoplanet]]ary companion in the northern [[constellation]] of [[Draco (constellation)|Draco]]. The system is located at a distance of 21.1 [[light-year]]s (6.4 [[Parsec|parsecs]]) from the [[Sun]] based on [[stellar parallax|parallax]],<ref name="GaiaDR3"/> but is drifting closer with a [[radial velocity]] of −13 km/s.<ref name=Fouqué_et_al_2018/> It is too faint to be visible to the naked eye, having an [[apparent visual magnitude]] of 10.13<ref name=Anderson_Francis_2012/> and an [[absolute magnitude]] of 11.06.<ref name=Anderson_Francis_2012/>
This is an [[M-type main-sequence star]] with a [[stellar classification]] of M1.5V.<ref name=Alonso-Floriano_et_al_2015/> It is spinning slowly with a [[rotation period]] of roughly 78 days, and has a low [[magnetic activity]] level.<ref name="Suárez Mascareño2017"/> The star has about a quarter of the mass and size of the Sun,<ref name=Khata_et_al_2020/> and the [[metallicity|metal]] content is 40% the abundances in the Sun's atmosphere. It is radiating just 1.5% of the luminosity of the Sun from its [[photosphere]] at an [[effective temperature]] of 3,557 K.<ref name=Fouqué_et_al_2018/>
==Planetary system== On May 18, 2017, a planet was detected orbiting GJ 625 by the [[HARPS-N]] telescope. The planet, GJ 625 b, orbits near the inner edge of the optimistic [[circumstellar habitable zone]] of its star, and the discoverers speculate it may support liquid water, depending on atmospheric conditions.<ref name="Suárez Mascareño2017"/> Based on the habitable zone model of Kopparapu et al. 2013, the planet is not considered to be in the habitable zone as it would likely experience a [[runaway greenhouse effect]], similar to [[Venus]].<ref name="Kopparapu2013"/><ref>{{cite web |url=https://personal.ems.psu.edu/~ruk15/planets/ |title=Calculation of Habitable Zones |last=Kopparapu |first=Ravi Kumar |access-date=20 November 2023 |archive-date=20 November 2023 |archive-url=https://web.archive.org/web/20231120171738/https://personal.ems.psu.edu/~ruk15/planets/ |url-status=live }}</ref><ref>{{cite web |url=http://hzgallery.org/3417_2.png |title=GJ 625 |website=hzgallery.org |access-date=15 September 2022 |archive-date=15 September 2022 |archive-url=https://web.archive.org/web/20220915203211/http://hzgallery.org/3417_2.png |url-status=live }}</ref><ref>{{cite web |url=https://www.drewexmachina.com/2017/05/22/habitable-planet-reality-check-is-gj-625b-a-super-earth-or-a-super-venus/ |title=Habitable Planet Reality Check: Is GJ 625b a Super-Earth or a Super-Venus? |last=LePage |first=Andrew |date=22 May 2017 |website=drewexmachina.com |access-date=15 September 2022 |archive-date=25 May 2017 |archive-url=https://web.archive.org/web/20170525091921/https://www.drewexmachina.com/2017/05/22/habitable-planet-reality-check-is-gj-625b-a-super-earth-or-a-super-venus/ |url-status=live }}</ref>
Since the star is considered quiescent (having a low [[X-ray astronomy|X-ray]] emission and [[flare star|flare]] rate), the radio emission from the system may be [[aurora]]l in nature and coming from a short-period planet. Further observations will be needed to confirm this.<ref name=Pope_et_al_2021/>
{{OrbitboxPlanet begin | table_ref = <ref name="Suárez Mascareño2017"/> }} {{OrbitboxPlanet | exoplanet = b | mass_earth = {{val|2.82|0.51|p=≥}} | period = {{val|14.628|0.012|0.013}} | semimajor = {{val|0.078361|0.000044|0.000046}} | eccentricity = {{val|0.13|0.12|0.09}} }} {{Orbitbox end}}
==References== {{Reflist|refs=
<ref name="GaiaDR3">{{Cite Gaia DR3|1428427236986209024}}</ref>
<ref name=SIMBAD>{{cite simbad | title=G 202-48 | access-date=2021-11-21 }}</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="Suárez Mascareño2017">{{cite journal | title=HADES RV Programme with HARPS-N at TNG. V. A super-Earth on the inner edge of the habitable zone of the nearby M dwarf GJ 625 | url=https://www.aanda.org/articles/aa/full_html/2017/09/aa30957-17/aa30957-17.html | last1=Suárez Mascareño | first1=A. | last2=González Hernández | first2=J. I. | last3=Rebolo | first3=R. | last4=Velasco | first4=S. | last5=Toledo-Padrón | first5=B. | last6=Affer | first6=L. | last7=Perger | first7=M. | last8=Micela | first8=G. | last9=Ribas | first9=I. | last10=Maldonado | first10=J. | last11=Leto | first11=G. | last12=Zanmar Sanchez | first12=R. | last13=Scandariato | first13=G. | last14=Damasso | first14=M. | last15=Sozzetti | first15=A. | last16=Esposito | first16=M. | last17=Covino | first17=E. | last18=Maggio | first18=A. | last19=Lanza | first19=A. F. | last20=Desidera | first20=S. | last21=Rosich | first21=A. | last22=Bignamini | first22=A. | last23=Claudi | first23=R. | last24=Benatti | first24=S. | last25=Borsa | first25=F. | last26=Pedani | first26=M. | last27=Molinari | first27=E. | last28=Morales | first28=J. C. | last29=Herrero | first29=E. | last30=Lafarga | first30=M. | display-authors=1 | journal=Astronomy and Astrophysics | volume=605 | at=A92 | year=2017 | arxiv=1705.06537 | bibcode=2017A&A...605A..92S | doi=10.1051/0004-6361/201730957 | s2cid=119003137 | access-date=2018-10-06 | archive-date=2023-09-23 | archive-url=https://web.archive.org/web/20230923015117/https://www.aanda.org/articles/aa/full_html/2017/09/aa30957-17/aa30957-17.html | url-status=live }}</ref>
<ref name="SchweitzerPassegger2019">{{cite journal | title=The CARMENES search for exoplanets around M dwarfs. Different roads to radii and masses of the target stars | display-authors=1 | last1=Schweitzer | first1=A. | last2=Passegger | first2=V. M. | last3=Cifuentes | first3=C. | last4=Béjar | first4=Victor J. S. | last5=Cortés-Contreras | first5=M. | last6=Caballero | first6=José A. | last7=del Burgo | first7=Carlos | last8=Czesla | first8=Stefan | last9=Kürster | first9=Martin | last10=Montes | first10=David | last11=Zapatero-Osorio | first11=María Rosa | last12=Ribas | first12=Ignasi | last13=Reiners | first13=Ansgar | last14=Quirrenbach | first14=Andreas | last15=Amado | first15=Pedro J. | last16=Aceituno | first16=J. | last17=Anglada-Escudé | first17=Guillem | last18=Bauer | first18=Florian F. | last19=Dreizler | first19=Stefan | last20=Jeffers | first20=Sandra V. | last21=Guenther | first21=E. W. | last22=Henning | first22=Thomas K. | last23=Kaminski | first23=Adrian | last24=Lafarga | first24=M. | last25=Marfil | first25=E. | last26=Morales | first26=Juan Carlos | last27=Schmitt | first27=Jürgen H. M. M. | last28=Seifert | first28=Walter | last29=Solano | first29=E. | last30=Tabernero | first30=H. M. | last31=Zechmeister | first31=Mathias | journal=Astronomy & Astrophysics | volume=625 | id=A68 | pages=16 | date=May 2019 | arxiv=1904.03231 | bibcode=2019A&A...625A..68S | doi=10.1051/0004-6361/201834965 | s2cid=102351979 }} [https://vizier.u-strasbg.fr/viz-bin/VizieR-5?-ref=VIZ609c64ba24592f&-out.add=.&-source=J/A%2bA/625/A68/tableb1&recno=200 VizieR entry] {{Webarchive|url=https://web.archive.org/web/20210512233833/https://vizier.u-strasbg.fr/viz-bin/VizieR-5?-ref=VIZ609c64ba24592f&-out.add=.&-source=J/A%2BA/625/A68/tableb1&recno=200 |date=2021-05-12 }}</ref>
<ref name=Alonso-Floriano_et_al_2015>{{cite journal | title=CARMENES input catalogue of M dwarfs. I. Low-resolution spectroscopy with CAFOS | last1=Alonso-Floriano | first1=F. J. | last2=Morales | first2=J. C. | last3=Caballero | first3=J. A. | last4=Montes | first4=D. | last5=Klutsch | first5=A. | last6=Mundt | first6=R. | last7=Cortés-Contreras | first7=M. | last8=Ribas | first8=I. | last9=Reiners | first9=A. | last10=Amado | first10=P. J. | last11=Quirrenbach | first11=A. | last12=Jeffers | first12=S. V. | display-authors=1 | journal=Astronomy & Astrophysics | volume=577 | id=A128 | pages=19 | date=May 2015 | doi=10.1051/0004-6361/201525803 | arxiv=1502.07580 | bibcode=2015A&A...577A.128A | s2cid=53135130 }}</ref>
<ref name=Fouqué_et_al_2018>{{cite journal | title=SPIRou Input Catalogue: global properties of 440 M dwarfs observed with ESPaDOnS at CFHT | last1=Fouqué | first1=Pascal | last2=Moutou | first2=Claire | last3=Malo | first3=Lison | last4=Martioli | first4=Eder | last5=Lim | first5=Olivia | last6=Rajpurohit | first6=Arvind | last7=Artigau | first7=Etienne | last8=Delfosse | first8=Xavier | last9=Donati | first9=Jean-François | last10=Forveille | first10=Thierry | last11=Morin | first11=Julien | last12=Allard | first12=France | last13=Delage | first13=Raphaël | last14=Doyon | first14=René | last15=Hébrard | first15=Elodie | last16=Neves | first16=Vasco | display-authors=1 | journal=Monthly Notices of the Royal Astronomical Society | volume=475 | issue=2 | pages=1960–1986 | date=April 2018 | doi=10.1093/mnras/stx3246 | doi-access=free | arxiv=1712.04490 | bibcode=2018MNRAS.475.1960F }}</ref>
<ref name=Khata_et_al_2020>{{cite journal | title=Understanding the physical properties of young M dwarfs: NIR spectroscopic studies | display-authors=1 | last1=Khata | first1=Dhrimadri | last2=Mondal | first2=Soumen | last3=Das | first3=Ramkrishna | last4=Ghosh | first4=Supriyo | last5=Ghosh | first5=Samrat | journal=Monthly Notices of the Royal Astronomical Society | volume=493 | issue=3 | pages=4533–4550 | date=April 2020 | doi=10.1093/mnras/staa427 | doi-access=free | arxiv=2002.05762 | bibcode=2020MNRAS.493.4533K }}</ref>
<ref name=Pope_et_al_2021>{{cite journal | title=The TESS View of LOFAR Radio-emitting Stars | display-authors=1 | last1=Pope | first1=Benjamin J. S. | last2=Callingham | first2=Joseph R. | last3=Feinstein | first3=Adina D. | last4=Günther | first4=Maximilian N. | last5=Vedantham | first5=Harish K. | last6=Ansdell | first6=Megan | last7=Shimwell | first7=Timothy W. | journal=The Astrophysical Journal Letters | volume=919 | issue=1 | id=L10 | pages=8 | date=September 2021 | doi=10.3847/2041-8213/ac230c | arxiv=2110.04759 | bibcode=2021ApJ...919L..10P | s2cid=238583021 | doi-access=free }}</ref>
<ref name="Kopparapu2013">{{cite journal |title=Habitable Zones Around Main-Sequence Stars: New Estimates |first1=Ravi Kumar |last1=Kopparapu |first2=Ramses |last2=Ramirez |first3=James F. |last3=Kasting |first4=Vincent |last4=Eymet |first5=Tyler D. | last5=Robinson |first6=Suvrath | last6=Mahadevan |first7=Ryan C. | last7=Terrien |first8=Shawn | last8=Domagal-Goldman |first9=Victoria | last9=Meadows |first10=Rohit | last10=Deshpande |display-authors=1 |date=2013|arxiv=1301.6674 |bibcode=2013ApJ...765..131K|doi = 10.1088/0004-637X/765/2/131 | volume=765 |issue=2 | journal=The Astrophysical Journal | pages=131|s2cid=76651902 }}</ref>
}}
{{Stars of Draco}}
[[Category:M-type main-sequence stars]] [[Category:Planetary systems with one confirmed planet]] [[Category:Draco (constellation)]] [[Category:Gliese and GJ objects|0625]] [[Category:Hipparcos objects|080459]]