HD 102365
{{Short description|Binary star system in the constellation Centaurus}}
{{Starbox begin}}
{{Starbox observe 2s
| epoch = J2000
| constell = Centaurus
| component1 = A
| dec1 = {{DEC|−40|30|01.2859}}
| component2 = B
| dec2 = {{DEC|−40|29|47.6048}}
}}
{{Starbox character
| class = G2V + M4V
| variable =
}}
{{Starbox astrometry
| component1 = A
| radial_v = {{val|16.94|0.12}}
| prop_mo_ra = −1530.971
| prop_mo_dec = +403.287
| parallax = 107.3024
| p_error = 0.0873
| component2 = B
| radial_v2 = {{val|17.23|0.27}}
| prop_mo_ra2 = −1534.679
| prop_mo_dec2 = +381.396
| parallax2 = 107.4237
| p_error2 = 0.0351
| absmag_v2 =
}}
{{Starbox detail
| component1 = A
| mass = {{Val|0.84|0.04|0.03}}
| luminosity = {{Val|0.86|0.05}}
| temperature = {{Val|5594|49|50|fmt=commas}}
}}
{{Starbox catalog
| names = {{odlist | name=66 G. Cen | GJ=442 | HR=4523 | CD=−39°7301 | HD=102365 | LHS=311 | LTT=4373 | PLX=2725.00 | SAO=223020 | HIP=57443 }}
| component2 = B
| names2 = {{odlist | LHS=313}}, VB 5
}}
{{Starbox reference
| Simbad=LHS+311
| sn=A
| Simbad2=GJ+442+B
| sn2=B
| NSTED=HD-102365
| ARICNS=00904
}}
{{Starbox end}}
HD 102365 (66 G. Centauri) is a binary star system that is located in the northeastern part of the Centaurus constellation, at a distance of about {{Convert|30.4|ly|pc|lk=on|abbr=off}} from the Solar System. The larger member of the system is a G-type star that is smaller than the Sun but of similar mass. It has a common proper motion companion that was discovered by W. J. Luyten in 1960. This M-type star appears to be in a wide orbit around the primary at a current separation of about 211 astronomical units (AU), (or 211 times the separation of the Earth from the Sun). By comparison, Neptune orbits at an average distance of 30 AU.
Description
The stellar classification for the primary star in this system is G2V; the same as the Sun. That of the red dwarf companion is M4V. The primary star has an estimated 84% the mass of the Sun, 99% of the Sun's radius, and 86% of the Sun's luminosity. It is a slow rotator, with a projected rotational velocity of 0.5 km/s. Age estimates range from 4.5 to 5.7 billion years (Gyr) up to 7.1 Gyr or 9.48 Gyr. Compared to the Sun, it only has about 52% of the abundance of elements other than hydrogen and helium; what astronomers term the metallicity of a star.
This star system has a relatively large proper motion. The HR 4523 system is presently located within the Epsilon Indi Moving Group, although it gives itself away as an interloper, since the star is older and has a different composition than the group members. It has space velocity components {{nowrap|[U, V, W]}} = {{nowrap|[−67, −40, +4] km/s}}.
Planetary system
The primary star is believed to be orbited by a Neptune-like planet with a minimum mass 16 times that of the Earth. The orbital period of this planet is 122.1 days. No other planets have been discovered orbiting this star. While a 2013 study was unable to confirm this planet, it was confirmed by a 2023 study.{{rp|27}}
An examination of this system in the infrared did not reveal an excess emission that would otherwise suggest the presence of a circumstellar debris disk.
{{OrbitboxPlanet begin
}}
{{OrbitboxPlanet
| exoplanet = b
| mass_earth = {{val|9.34|1.52|1.5|p=≥}}
| period = {{val|121.3|0.25}}
| semimajor = {{val|0.46|0.04}}
| eccentricity = {{val|0.28|0.15}}
}}
{{Orbitbox end}}
References
{{reflist|refs=
{{Cite Gaia DR3|5381537023379295232}}
{{Cite Gaia DR3|5381537023379295744}}
{{cite constellation|HD 102365}}
| title=Setting the Stage for the Search for Life with the Habitable Worlds Observatory: Properties of 164 Promising Planet-survey Targets
| last1=Harada | first1=Caleb K. | last2=Dressing | first2=Courtney D.
| last3=Kane | first3=Stephen R. | last4=Ardestani | first4=Bahareh Adami
| journal=The Astrophysical Journal Supplement Series
| volume=272 | issue=2 | at=id. 30 | date=June 2024
| doi=10.3847/1538-4365/ad3e81 | doi-access=free | arxiv=2401.03047
| bibcode=2024ApJS..272...30H | display-authors=1 }}
{{cite simbad | title=HD 102365 | access-date=2011-10-11 }}
| url=http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=V%2F135%2Fcatalog
| last=Gould | first=Benjamin Apthorp | date=1879
| title=Uranometria Argentina catalog of bright southern stars
| journal=Resultados del Observatorio Nacional Argentino en Cordoba
| volume=1 | publication-place=Buenos Aires
| bibcode=1879RNAO....1.....G | access-date=2012-05-08
}}
For a metallicity of [Fe/H] = −0.28 dex, the proportion of metals is given by 10−0.28, or 52%.
{{cite journal |last1=Zechmeister |first1=M. |last2=Kürster |first2=M. |display-authors=etal |date=April 2013 |title=The planet search programme at the ESO CES and HARPS. IV. The search for Jupiter analogues around solar-like stars |journal=Astronomy & Astrophysics |volume=552 |issue= |pages=A78 |doi=10.1051/0004-6361/201116551 |arxiv=1211.7263 |bibcode=2013A&A...552A..78Z|s2cid=53694238 }}
{{cite journal |last1=Laliotis |first1=Katherine |last2=Burt |first2=Jennifer A. |display-authors=etal |date=February 2023 |title=Doppler Constraints on Planetary Companions to Nearby Sun-like Stars: An Archival Radial Velocity Survey of Southern Targets for Proposed NASA Direct Imaging Missions |journal=The Astronomical Journal |volume= 165|issue= 4|page=176 |doi= 10.3847/1538-3881/acc067|arxiv=2302.10310 |bibcode=2023AJ....165..176L |doi-access=free }}
}}
External links
- {{citation | title=HR 4523 AB | publisher=SolStation | url=http://www.solstation.com/stars/hr4523ab.htm | access-date=2011-10-11 }}
{{Stars of Centaurus}}
{{DEFAULTSORT:HD 102365}}
Category:G-type main-sequence stars
Category:Planetary systems with one confirmed planet