| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Carina |
| Right ascension | 07 53 41.3193 |
| Declination | −63° 38′ 50.353″ |
| Apparent magnitude (V) | 7.97 |
| Characteristics | |
| Spectral type | G5V + M7–8 + L2–3 |
| B−V color index | 0.672±0.012 |
| Astrometry | |
| Radial velocity (Rv) | 42.57±0.16 km/s |
| Proper motion (μ) | RA: −123.633±0.065 mas/yr Dec.: 146.578±0.073 mas/yr |
| Parallax (π) | 28.4445 ± 0.0317 mas |
| Distance | 114.7 ± 0.1 ly (35.16 ± 0.04 pc) |
| Absolute magnitude (MV) | 5.22 |
| Details | |
| HD 65216 A | |
| Mass | 0.95±0.01 M☉ |
| Radius | 0.864±0.003 R☉ |
| Luminosity | 0.716±0.001 L☉ |
| Surface gravity (log g) | 4.53±0.01 cgs |
| Temperature | 5,718±8 K |
| Metallicity | −0.17 dex |
| Rotational velocity (v sin i) | 1.308 km/s |
| Age | 1.7±0.5 Gyr |
| Other designations | |
| CD−63°359, HD 65216, HIP 38558, SAO 250002, WDS J07537-6339A | |
| Database references | |
| SIMBAD | data |
HD 65216 is a triple star system with two exoplanetary companions in the southern constellation of Carina. With an apparent visual magnitude of 7.97 it cannot be readily seen without technical aid, but with binoculars or telescope it should be visible. The system is located at a distance of 114.7 light-years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of 42.6 km/s.
The primary, component A, is an ordinary G-type main-sequence star with a stellar classification of G5V. It is nearly two billion years old and is spinning with a projected rotational velocity of 1.3 km/s. The star has 95% of the mass and 86% of the radius of the Sun. It is radiating 72% of the luminosity of the Sun from its photosphere at an effective temperature of 5,718 K.
In 2008 a co-moving binary system of low mass companions were discovered at an angular separation of 7″ from the primary, which is equivalent to a projected separation of 253 AU at the distance of HD 65216. Component B is of class M7–8 (0.089 M☉) while component C is class L2–3 (0.078 M☉); both have a mass close to the sub-stellar limit. The pair have a projected separation of 6 AU from each other.
Planetary system
An extrasolar planet (designated as HD 65216 b) was discovered orbiting the primary in 2003. A second much more distant planet was suspected since 2013, but was discovered on a completely different orbit in 2019.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | ≥1.295±0.062 MJ | 1.301±0.020 | 577.6±1.328 | 0.27±0.02 | — | — |
| c | ≥2.03±0.11 MJ | 5.75±0.09 | 5370±20 | 0.17±0.04 | — | — |
See also
References
- ^ Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data 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 source at VizieR.
- ^ Anderson, 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. S2CID 119257644.
- ^ Houk, Nancy (1979). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 1. Ann Arbor, Michigan: Department of Astronomy, University of Michigan. Bibcode:1978mcts.book.....H.
- ^ Mugrauer, M.; Seifahrt, A.; Neuhäuser, R. (July 2007). "The multiplicity of planet host stars - new low-mass companions to planet host stars". Monthly Notices of the Royal Astronomical Society. 378 (4): 1328–1334. arXiv:0704.1767. Bibcode:2007MNRAS.378.1328M. doi:10.1111/j.1365-2966.2007.11858.x. S2CID 14227351.
- ^ 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.
- ^ Costa Silva, A. R.; et al. (February 2020). "Chemical abundances of 1111 FGK stars from the HARPS-GTO planet search sample. III. Sulfur". Astronomy & Astrophysics. 634: 10. arXiv:1912.08659. Bibcode:2020A&A...634A.136C. doi:10.1051/0004-6361/201936523. S2CID 209405391. A136.
- "HD 65216". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-09-26.
- Mayor, M.; et al. (2004). "The CORALIE survey for southern extra-solar planets XII. Orbital solutions for 16 extra-solar planets discovered with CORALIE". Astronomy and Astrophysics. 415 (1): 391–402. arXiv:astro-ph/0310316. Bibcode:2004A&A...415..391M. doi:10.1051/0004-6361:20034250.
- Wittenmyer, Robert A.; et al. (2013). "Forever Alone? Testing Single Eccentric Planetary Systems for Multiple Companions". The Astrophysical Journal Supplement Series. 208 (1): 2. arXiv:1307.0894. Bibcode:2013ApJS..208....2W. doi:10.1088/0067-0049/208/1/2. S2CID 14109907.
- ^ Wittenmyer, Robert A.; et al. (2019). "Truly eccentric – I. Revisiting eight single-eccentric planetary systems". Monthly Notices of the Royal Astronomical Society. 484 (4): 5859–5867. arXiv:1901.08471. Bibcode:2019MNRAS.484.5859W. doi:10.1093/mnras/stz290.
External links
- "Notes for star HD 65216". Extrasolar Planets Encyclopaedia. Archived from the original on July 2, 2007. Retrieved 2008-08-22.
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