Astronomy:HD 156279

From HandWiki
(Redirected from Astronomy:HD 156279 c)
Short description: Star in the constellation Draco
HD 156279
Observation data
Equinox J2000.0]] (ICRS)
Constellation Draco[1]
Right ascension  17h 12m 23.204816s[2]
Declination +63° 21′ 07.531205″[2]
Apparent magnitude (V) 8.167±0.013[3]
Characteristics
Evolutionary stage main-sequence[4]
Spectral type K0[3] or G6[4]
Apparent magnitude (R) 7.60[1]
Apparent magnitude (G) 7.8657[2]
Apparent magnitude (J) 6.677±0.018[1]
B−V color index 0.801±0.014[1]
Astrometry
Radial velocity (Rv)−20.144±0.161[5] km/s
Proper motion (μ) RA: −1.879±0.024[2] mas/yr
Dec.: 160.429±0.027[2] mas/yr
Parallax (π)27.6756 ± 0.0200[2] mas
Distance117.85 ± 0.09 ly
(36.13 ± 0.03 pc)
Absolute magnitude (MV)5.25[1]
Details
Mass0.999+0.046
−0.045
[6] M☉
Radius0.94±0.02[7] R☉
Luminosity0.70±0.01[7] L☉
Surface gravity (log g)4.45±0.03[7] cgs
Temperature5,449±31[7] K
Metallicity [Fe/H]0.14±0.01[3] dex
Rotational velocity (v sin i)2.51±1[4] km/s
Age7.4±2.2[7] Gyr
Other designations
BD+63 1335, Gaia DR2 1631084478574318976, HD 156279, HIP 84171, SAO 17390, PPM 20265, NLTT 44404, TYC 4202-656-1, 2MASS J17122319+6321074[8]
Database references
SIMBADdata

HD 156279 is a star with a pair of orbiting exoplanets[9] located in the northern constellation of Draco.[1] It has various alternate designations, including HIP 84171 and BD+63 1335. Parallax measurements yield a distance of 118 light years from the Sun,[2] but it is drifting closer with a radial velocity of −20 km/s.[5] Despite an absolute magnitude of 5.25,[1] at that distance the star is too faint to be visible to the naked eye with an apparent visual magnitude of 8.17.[3] It is presumed to be a single star, as in 2019 all imaging surveys have failed to find any stellar companions.[3]

The spectrum of HD 156279 has a stellar classification of G6[4] or K0,[3] depending on the study. Hence it presents as an ordinary main sequence star[4] of the late G-type or early K-type. The star has 93% of the mass of the Sun and 94% of the Sun's radius. HD 156279 is roughly seven[7] billion years old and is spinning with a projected rotational velocity of 2.5 km/s.[4] Based on the abundance of iron, this star is slightly enriched in heavy elements, having 140% of the solar abundance.[3] It is radiating 70%[7] of the luminosity of the Sun from its photosphere at an effective temperature of 5,449 K.[7]

Planetary system

Orbiting HD 156279 are two superjovian planets, the inner HD 156279 b (discovered in 2011)[4] and outer HD 156279 c (discovered in 2016).[9] In 2022, the inclination and true mass of HD 156279 c were measured for the first time, using the astrometry technique.[10]

The HD 156279 planetary system[6]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(years)
Eccentricity Inclination Radius
b ≥ 9.82±0.29 MJ 0.5126+0.0077
−0.0078
0.365235(10) 0.6479+0.00070
−0.00077
— —
c 10.53+0.65
−0.59
 MJ
5.570+0.086
−0.084
13.093±0.081 0.2602+0.0047
−0.0048
110.9+6.9
−9.4
°
—

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode: 2012AstL...38..331A. 
  2. ↑ 2.0 2.1 2.2 2.3 2.4 2.5 Vallenari, A. et al. (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics. doi:10.1051/0004-6361/202243940  Gaia DR3 record for this source at VizieR.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 Biller, B. et al. (2019), "A high binary fraction for the most massive close-in giant planets and brown dwarf desert members", Monthly Notices of the Royal Astronomical Society 485 (4): 4967–4996, doi:10.1093/mnras/stz671, Bibcode: 2019MNRAS.485.4967F. 
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 Díaz, Rodrigo F. et al. (2012), "The SOPHIE search for northern extrasolar planets IV. Massive companions in the planet-brown dwarf boundary", Astronomy & Astrophysics A113: 538, doi:10.1051/0004-6361/201117935, Bibcode: 2012A&A...538A.113D. 
  5. ↑ 5.0 5.1 Carrera, R. et al. (February 2022), "OCCASO. IV. Radial velocities and open cluster kinematics", Astronomy & Astrophysics 658, doi:10.1051/0004-6361/202141832, A14, Bibcode: 2022A&A...658A..14C. 
  6. ↑ 6.0 6.1 Template:Ciation.
  7. ↑ 7.0 7.1 7.2 7.3 7.4 7.5 7.6 7.7 Bonfanti, A. et al. (2016), "Age consistency between exoplanet hosts and field stars", Astronomy & Astrophysics 585: 14, doi:10.1051/0004-6361/201527297, A5, Bibcode: 2016A&A...585A...5B. 
  8. ↑ "HD 156279". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+156279. 
  9. ↑ 9.0 9.1 Bryan, Marta L. et al. (2016), "Statistics of long period gas giant planets in known planetary systems", The Astrophysical Journal 821 (2): 89, doi:10.3847/0004-637X/821/2/89, Bibcode: 2016ApJ...821...89B. 
  10. ↑ Feng, Fabo et al. (August 2022), "3D Selection of 167 Substellar Companions to Nearby Stars", The Astrophysical Journal Supplement Series 262 (21): 21, doi:10.3847/1538-4365/ac7e57, Bibcode: 2022ApJS..262...21F.