HD 45364
| Observation data EpochJ2000.0EquinoxJ2000.0 | |
|---|---|
| Constellation | Canis Major |
| Right ascension | 06h25m38.47443s[1] |
| Declination | −31° 28′ 51.4285″[1] |
| Apparent magnitude(V) | 8.08[2] |
| Characteristics | |
| Spectral type | G8V[3] |
| B−Vcolor index | 0.719±0.015[2] |
| V−Rcolor index | 0.01 |
| Astrometry | |
| Radial velocity(Rv) | +16.392±0.0004[1]km/s |
| Proper motion(μ) | RA:+52.182[1]mas/yr Dec.:−11.926[1]mas/yr |
| Parallax(π) | 29.0797 ± 0.0316mas[1] |
| Distance | 112.2 ± 0.1ly (34.39 ± 0.04pc) |
| Absolute magnitude(MV) | +5.51[2] |
| Details[4] | |
| Mass | 0.88±0.02M☉ |
| Radius | 0.82±0.01R☉ |
| Luminosity | 0.562±0.004L☉ |
| Surface gravity(logg) | 4.55±0.03cgs |
| Temperature | 5,540±31K |
| Metallicity[Fe/H] | −0.14±0.03[2]dex |
| Rotational velocity(vsini) | 1.672±0.665[5]km/s |
| Age | 3.4±2.7Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
HD 45364is astarin the southernconstellationofCanis Major.It is too faint to be visible to the naked eye, having anapparent visual magnitudeof 8.08.[2]The distance to this system is 112light yearsbased onparallax.[1]It is drifting further away from the Sun with aradial velocityof +16.4 km/s,[1]having come within 49 light-years some 1.5 million years ago.[2]
This object is an ordinaryG-type main-sequence starwith astellar classificationof G8V,[3]which indicates it is generating energy throughcorehydrogen fusion.It is around 3.4 billion years old and is spinning with aprojected rotational velocityof 1.7 km/s.[5]The star has 88% of themass of the Sunand 82% of theSun's radius.It is radiating 56% of theluminosity of the Sunfrom itsphotosphereat aneffective temperatureof 5,540 K. As of August 2008 there are two confirmedextrasolar planets(or exoplanets) orbiting around it.[7]
Planetary system[edit]
HD 45364 is one of only a relative few systems that have had more than oneexoplanetdiscovered in its orbit. The two planets, HD 45364 b and HD 45364 c respectively, were both discovered in August 2008 using theradial velocity method.The pair was initially believed to be orbiting the host star with a 3:2mean motion resonance,[7]which means the inner planet is completing three orbits for every two orbits of the outer planet.
It was difficult to explain how such resonant configuration of planetary orbits could evolve,[8]mainly due to too high (4-5 times) orbital eccentrities, although planetary system formation models involving hydrodynamic effects were proposed.[9]
As in 2022, refined radial-velocity data shows the planetary orbits are more circular and widely spaced, therefore planets are slightly out of mean motion resonance state.[10]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥0.1893+0.0062 −0.006MJ |
0.6793+0.0016 −0.0015 |
225.79+0.81 −0.76 |
0.067±0.016 | — | — |
| c | ≥0.5490+0.0075 −0.0074MJ |
0.9020±0.0010 | 345.43+0.54 −0.57 |
0.019+0.011 −0.010 |
— | — |
References[edit]
- ^abcdefghBrown, A. G. A.;et al. (Gaia collaboration) (August 2018)."GaiaData Release 2: Summary of the contents and survey properties ".Astronomy & Astrophysics.616.A1.arXiv:1804.09365.Bibcode:2018A&A...616A...1G.doi:10.1051/0004-6361/201833051.Gaia DR2 record for this sourceatVizieR.
- ^abcdefAnderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation".Astronomy Letters.38(5): 331.arXiv:1108.4971.Bibcode:2012AstL...38..331A.doi:10.1134/S1063773712050015.S2CID119257644.
- ^abGray, R. O.; et al. (July 2006). "Contributions to the Nearby Stars (NStars) Project: spectroscopy of stars earlier than M0 within 40 pc-The Southern Sample".The Astronomical Journal.132(1): 161–170.arXiv:astro-ph/0603770.Bibcode:2006AJ....132..161G.doi:10.1086/504637.S2CID119476992.
- ^Bonfanti, A.; et al. (2015)."Revising the ages of planet-hosting stars".Astronomy and Astrophysics.575.A18.arXiv:1411.4302.Bibcode:2015A&A...575A..18B.doi:10.1051/0004-6361/201424951.S2CID54555839.
- ^abSoto, M. G.; Jenkins, J. S. (July 2018). "Spectroscopic Parameters and atmosphEric ChemIstriEs of Stars (SPECIES). I. Code description and dwarf stars catalogue".Astronomy & Astrophysics.615:28.arXiv:1801.09698.Bibcode:2018A&A...615A..76S.doi:10.1051/0004-6361/201731533.S2CID119107228.A76.
- ^"HD 45364".SIMBAD.Centre de données astronomiques de Strasbourg.Retrieved2019-12-19.
- ^abCorreia, A. C. M.; et al. (2009)."The HARPS search for southern extra-solar planets XVI. HD 45364, a pair of planets in a 3:2 mean motion resonance".Astronomy and Astrophysics.496(2): 521–526.arXiv:0902.0597.Bibcode:2009A&A...496..521C.doi:10.1051/0004-6361:200810774.S2CID119235349.
- ^Rein, H.; et al. (2010)."The dynamical origin of the multi-planetary system HD 45364"(abstract).Astronomy and Astrophysics.510(1): A4.arXiv:0910.5082.Bibcode:2010A&A...510A...4R.doi:10.1051/0004-6361/200913208.S2CID118459467.(web preprint)
- ^Correa-Otto, J. (2013)."A new scenario for the origin of the 3/2 resonant system HD 45364".Astronomy and Astrophysics.560(65): A65.arXiv:1307.1822.Bibcode:2013A&A...560A..65C.doi:10.1051/0004-6361/201321917.S2CID51897058.
- ^abLi, Zhexing; Kane, Stephen R.; Dalba, Paul A.; Howard, Andrew W.; Isaacson, Howard T. (2022), "New Dynamical State and Habitability of the HD 45364 Planetary System",The Astronomical Journal,164(4): 163,arXiv:2209.00120,Bibcode:2022AJ....164..163L,doi:10.3847/1538-3881/ac8d63,S2CID251979687
