HD 68402

HD 68402
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Volans
Right ascension 08h 05m 23.69129s[1]
Declination −74° 24′ 37.4873″[1]
Apparent magnitude (V) 9.09 ± 0.02[2]
Characteristics
Spectral type G5 IV/V[3]
B−V color index +0.68[2]
Astrometry
Radial velocity (Rv)11.60 ± 0.49[4] km/s
Proper motion (μ) RA: −78.195 mas/yr[1]
Dec.: +78.973 mas/yr[1]
Parallax (π)12.7204 ± 0.0101 mas[1]
Distance256.4 ± 0.2 ly
(78.61 ± 0.06 pc)
Absolute magnitude (MV)+4.66[5]
Details[6]
Mass1.12 ± 0.05 M☉
Radius1.02 ± 0.05 R☉
Luminosity1.17+0.06
−0.07 L☉
Surface gravity (log g)4.43 ± 0.04[7] cgs
Temperature5,907 ± 68[7] K
Metallicity [Fe/H]+0.29 ± 0.10 dex
Rotational velocity (v sin i)2.9 ± 0.2 km/s
Age1 ± 0.9[7] Gyr
Other designations
CD−74° 392, CPD−74° 486, HD 68402, HIP 39589
Database references
SIMBADdata
Exoplanet Archivedata

HD 68402 is a solitary star located in the circumpolar constellation Volans. With an apparent magnitude of 9.09,[2] it is invisible to the naked eye but can be seen with an amateur telescope. This star is located at a distance of 256 light years based on its parallax shift but is drifting away at a rate of 11.60 km/s.[4]

HD 68402 has a classification of G5 IV/V,[3] which indicates that it is a G5 star with the characteristics of a subgiant and main-sequence star. Contrary to its classification, it is actually a G1 dwarf.[6] At present it is slightly more massive than the Sun and has a similar radius to the latter.[6] It radiates at 1.17[6] times the luminosity of the Sun from its photosphere at an effective temperature of 5,907 K,[7] which gives it a yellow hue. At an age of 1 billion years HD 68402[7] has a projected rotational velocity of almost 3 km/s and is metal rich like most planetary hosts (1.94 times to be exact).[6]

Planetary system

In 2017, a superjovian planet was discovered using doppler spectroscopy data from HARPS and CORALIE.[6] In 2023, the inclination and true mass of HD 68402 b were determined via astrometry.[8]

The HD 68402 planetary system[8]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(years) 		Eccentricity Inclination Radius
b 7.9+1.7
−1.5 MJ 		2.239+0.11
−0.075 		3.15+0.22
−0.14 		0.225+0.15
−0.082 		20.3+6.2
−4.1 or 159.7+4.1
−6.2° 		—

References

  1. ^ a b c d 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 Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (1 March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27 – L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361.
  3. ^ a b Houk, N.; Cowley, A. P. (1 January 1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations -90_ to -53_ƒ0. Bibcode:1975mcts.book.....H.
  4. ^ a b 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.
  5. ^ Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. ISSN 1063-7737. S2CID 255204555.
  6. ^ a b c d e f Jenkins, J. S.; Jones, H. R. A.; Tuomi, M.; Díaz, M.; Cordero, J. P.; Aguayo, A.; Pantoja, B.; Arriagada, P.; Mahu, R.; Brahm, R.; Rojo, P.; Soto, M. G.; Ivanyuk, O.; Becerra Yoma, N.; Day-Jones, A. C.; Ruiz, M. T.; Pavlenko, Y. V.; Barnes, J. R.; Murgas, F.; Pinfield, D. J.; Jones, M. I.; López-Morales, M.; Shectman, S.; Butler, R. P.; Minniti, D. (April 2017). "New planetary systems from the Calan–Hertfordshire Extrasolar Planet Search". Monthly Notices of the Royal Astronomical Society. 466 (1): 443–473. arXiv:1603.09391. Bibcode:2017MNRAS.466..443J. doi:10.1093/mnras/stw2811. ISSN 0035-8711.
  7. ^ a b c d e Adibekyan, V.; Santos, N. C.; Demangeon, O. D. S.; Faria, J. P.; Barros, S. C. C.; Oshagh, M.; Figueira, P.; Delgado Mena, E.; Sousa, S. G.; Israelian, G.; Campante, T.; Hakobyan, A. A. (May 2021). "Stellar clustering and orbital architecture of planetary systems". Astronomy & Astrophysics. 649: A111. arXiv:2102.12346. Bibcode:2021A&A...649A.111A. doi:10.1051/0004-6361/202040201. ISSN 0004-6361. S2CID 233707059.
  8. ^ a b Xiao, Guang-Yao; Liu, Yu-Juan; et al. (May 2023). "The Masses of a Sample of Radial-Velocity Exoplanets with Astrometric Measurements". Research in Astronomy and Astrophysics. 23 (5): 055022. arXiv:2303.12409. Bibcode:2023RAA....23e5022X. doi:10.1088/1674-4527/accb7e. S2CID 257663647.