HD 73526

Not to be confused with HD 73256.
HD 73526
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Vela
Right ascension 08h 37m 16.48335s[1]
Declination −41° 19′ 08.7904″[1]
Apparent magnitude (V) +8.99[2]
Characteristics
Evolutionary stage Main sequence[3]
Spectral type G6 V[3]
B−V color index 0.737±0.005[2]
Variable type Constant[3]
Astrometry
Radial velocity (Rv)+26.31±0.10[4] km/s
Proper motion (μ) RA: −60.993 mas/yr[1]
Dec.: 159.192 mas/yr[1]
Parallax (π)10.3311 ± 0.0144 mas[1]
Distance315.7 ± 0.4 ly
(96.8 ± 0.1 pc)
Absolute magnitude (MV)+4.1±0.2[5]
Absolute bolometric
magnitude (Mbol)		+3.7±0.2[5]
Details[4]
Mass1.01±0.04
1.14±0.15[6] M☉
Radius1.53±0.03[6] R☉
Luminosity2.14+0.68
−0.52 L☉
Surface gravity (log g)4.13±0.06 cgs
Temperature5,564±16 K
Metallicity [Fe/H]+0.23±0.02 dex
Rotational velocity (v sin i)1.69±0.26 km/s
Age9.59±1.00 Gyr
Other designations
CD−40° 4454, HD 73526, HIP 42282, SAO 220191[7]
Database references
SIMBADdata

HD 73526 is a star in the southern constellation of Vela. With an apparent visual magnitude of +8.99,[2] it is much too faint to be viewed with the naked eye. The star is located at a distance of approximately 316 light-years (97 parsecs) from the Sun based on parallax,[1] and is drifting further away with a radial velocity of +26 km/s.[4] It is a member of the thin disk population.[4]

The stellar classification of HD 73526 is G6 V,[3] indicating this is a G-type main-sequence star that, like the Sun, is generating energy through core hydrogen fusion. Based on its properties, it may be starting to evolve off the main sequence.[3] This star has slightly more mass than the Sun and a 53% greater radius. The abundance of iron in its atmosphere suggests the star's metallicity – what astronomers term the abundance of elements with higher atomic number than helium – is 70% greater than in the Sun. It is a much older star with an estimated age of nearly ten billion years, and is spinning slowly with a projected rotational velocity of 1.7 km/s. The star is radiating more than double the luminosity of the Sun from its photosphere at an effective temperature of 5,564 K.[4]

Planetary system

On June 13 2002,[8] a 2.1 MJ planet HD 73526 b was announced orbiting HD 73526 in an orbit just a little smaller than that of Venus' orbit around the Sun.[5] This planet receives an insolation 3.65 times that of Earth or 1.89 times that of Venus. This was a single planet system until 2006 when a 2.3 MJ second planet HD 73526 c was discovered. These planets forms a 2:1 orbital resonance with planet b.[3] In fact, they seem to be in a very deep resonance with very long timescale stability due to an ACR (Apsidal Corotation Resonance) the planets seem to satisfy.[9] Although these are minimum masses as the inclinations of these planets are unknown, orbital stability analysis indicates that the orbital inclinations of both planets are likely to be near 90°, making the minimum masses very close to the true masses of the planets.[10]

The HD 73526 planetary system[10]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(days) 		Eccentricity Inclination Radius
b ≥2.25±0.12 MJ 0.65±0.01 188.9±0.1 0.29±0.03 — —
c ≥2.25±0.13 MJ 1.03±0.02 379.1±0.5 0.28±0.05 — —

See also

References

  1. ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ a b c 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.
  3. ^ a b c d e f Tinney, C. G.; et al. (2006). "The 2 : 1 Resonant Exoplanetary System Orbiting HD 73526". The Astrophysical Journal. 647 (1): 594–599. arXiv:astro-ph/0602557. Bibcode:2006ApJ...647..594T. doi:10.1086/503706.
  4. ^ a b c d e Jofré, E.; et al. (2015). "Stellar parameters and chemical abundances of 223 evolved stars with and without planets". Astronomy & Astrophysics. 574. A50. arXiv:1410.6422. Bibcode:2015A&A...574A..50J. doi:10.1051/0004-6361/201424474. S2CID 53666931.
  5. ^ a b c Tinney, C. G.; et al. (2003). "Four New Planets Orbiting Metal-enriched Stars". The Astrophysical Journal. 587 (1): 423–428. arXiv:astro-ph/0207128. Bibcode:2003ApJ...587..423T. doi:10.1086/368068.
  6. ^ a b Stassun, Keivan G.; et al. (March 2017). "Accurate Empirical Radii and Masses of Planets and Their Host Stars with Gaia Parallaxes". The Astronomical Journal. 153 (3): 20. arXiv:1609.04389. Bibcode:2017AJ....153..136S. doi:10.3847/1538-3881/aa5df3. S2CID 119219062. 136.
  7. ^ "HD 73526". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-09-27.
  8. ^ Tinney, Chris (2007-09-07). "AAPS Discovered Planets". Anglo-Australian Planet Search. University of New South Wales. Retrieved 2018-04-17.
  9. ^ Pons, J.; Gallardo, T. (May 2024). "Secular evolution of resonant planets in the coplanar case. Application to the systems HD 73526 and HD 31527". Astronomy & Astrophysics. 685: A105. Bibcode:2024A&A...685A.105P. doi:10.1051/0004-6361/202348378. (Keywords – methods: numerical, celestial mechanics, planets and satellites: dynamical evolution and stability)
  10. ^ a b Wittenmyer, Robert A.; et al. (2014). "A Detailed Analysis of the HD 73526 2:1 Resonant Planetary System". The Astrophysical Journal. 780 (2). 140. arXiv:1311.6559. Bibcode:2014ApJ...780..140W. doi:10.1088/0004-637X/780/2/140.