HD 190984

HD 190984
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Pavo
Right ascension 20h 11m 30.71538s[1]
Declination −64° 37′ 13.6853″[1]
Apparent magnitude (V) 8.76[2]
Characteristics
Spectral type F8 V[3]
U−B color index +0.02[4]
B−V color index +0.54[4]
Astrometry
Radial velocity (Rv)+20.48±0.14[1] km/s
Proper motion (μ) RA: +0.193 mas/yr[1]
Dec.: +45.355 mas/yr[1]
Parallax (π)6.7060 ± 0.0153 mas[1]
Distance486 ± 1 ly
(149.1 ± 0.3 pc)
Absolute magnitude (MV)+2.25[5]
Details
Mass1.15±0.01[6] M☉
Radius2.31±0.09[7] R☉
Luminosity5.88±1.01[8] L☉
Surface gravity (log g)3.78±0.03[9] cgs
Temperature6,007±25[9] K
Metallicity−0.49±0.02[9]
Rotational velocity (v sin i)5[10] km/s
Age4.44±0.10[6] Gyr
Other designations
CD−64°1271, CPD−64°4030, HD 190984, HIP 99496, PPM 364454, 2MASS J20113069-6437136[11]
Database references
SIMBADdata
Exoplanet Archivedata

HD 190984, also known as HIP 99496, is a star located in the southern circumpolar constellation Pavo, the peacock. It has an apparent magnitude of 8.76,[2] making it readily visible in small telescopes, but not to the naked eye. Based on parallax measurements from the Gaia spacecraft, the object is estimated to be 486 light years away from the Solar System.[1] It appears to be receding with a heliocentric radial velocity of 20.3 km/s.[12]

Characteristics

This is an ordinary F-type main-sequence star with a stellar classification of F8 V,[3] generating energy via hydrogen fusion at its core. It has 115% the mass of the Sun[6] and an effective temperature of 6,007 K,[9] giving it a yellowish-white hue. However, HD 190984 has an enlarged radius of 2.31 R☉[7] and is 1.76 magnitudes[5] brighter than the main sequence, indicating that it may instead be a subgiant evolving towards the red giant branch;[1] it radiates 5.88 times the luminosity of the Sun[8] from its photosphere. Unlike most planetary hosts, HD 190984 has an iron abundance only 32% that of the Sun's, making it metal poor.[9] At an age of 4.44 billion years,[6] it is spinning with a projected rotational velocity of 5 km/s.[10]

Planetary system

A 2010 HARPS survey detected a super Jupiter orbiting the star. It has one of the longest periods of any exoplanet known at the time, but the value is poorly constrained.[12] Further observations are required to properly constrain the orbit. In 2023, the inclination and true mass of HD 190984 b were determined via astrometry.[13]

The HD 190984 planetary system[13]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(years) 		Eccentricity Inclination Radius
b 3.58+1.2
−0.45 MJ 		8.8+2.5
−1.4 		27.3+12.0
−6.1 		0.745+0.054
−0.047 		64+18
−23 or 116+23
−18° 		—

See also

References

  1. ^ a b c d e f g 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 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. eISSN 1562-6873. ISSN 1063-7737. S2CID 119257644.
  3. ^ a b Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations −90° to −53°. Bibcode:1975mcts.book.....H.
  4. ^ a b Carney, B. W. (September 1978). "Southern subdwarf photometry". The Astronomical Journal. 83: 1087. Bibcode:1978AJ.....83.1087C. doi:10.1086/112295. ISSN 0004-6256.
  5. ^ a b Gontcharov, G. A. (December 2012). "Dependence of kinematics on the age of stars in the solar neighborhood". Astronomy Letters. 38 (12): 771–782. arXiv:1606.08814. Bibcode:2012AstL...38..771G. doi:10.1134/S1063773712120031. ISSN 0320-0108. S2CID 118345778.
  6. ^ a b c d Gomes da Silva, J.; Santos, N. C.; Adibekyan, V.; Sousa, S. G.; Campante, T. L.; Figueira, P.; Bossini, D.; Delgado-Mena, E.; Monteiro, M. J. P. F. G.; de Laverny, P.; Recio-Blanco, A.; Lovis, C. (February 2021). "Stellar chromospheric activity of 1674 FGK stars from the AMBRE-HARPS sample". Astronomy & Astrophysics. 646: A77. arXiv:2012.10199. Bibcode:2021A&A...646A..77G. doi:10.1051/0004-6361/202039765. eISSN 1432-0746. ISSN 0004-6361.
  7. ^ a b Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. eISSN 1538-3881.
  8. ^ 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.
  9. ^ a b c d e Delgado Mena, E.; Tsantaki, M.; Adibekyan, V. Zh.; Sousa, S. G.; Santos, N. C.; González Hernández, J. I.; Israelian, G. (October 2017). "Chemical abundances of 1111 FGK stars from the HARPS GTO planet search program". Astronomy & Astrophysics. 606: A94. arXiv:1705.04349. Bibcode:2017A&A...606A..94D. doi:10.1051/0004-6361/201730535. eISSN 1432-0746. ISSN 0004-6361.
  10. ^ a b Nordström, B.; Mayor, M.; Andersen, J.; Holmberg, J.; Pont, F.; Jørgensen, B. R.; Olsen, E. H.; Udry, S.; Mowlavi, N. (16 April 2004). "The Geneva-Copenhagen survey of the Solar neighbourhood". Astronomy & Astrophysics. 418 (3): 989–1019. arXiv:astro-ph/0405198. Bibcode:2004A&A...418..989N. doi:10.1051/0004-6361:20035959. eISSN 1432-0746. ISSN 0004-6361.
  11. ^ "HD 190984". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved October 7, 2022.
  12. ^ a b Santos, N. C.; Mayor, M.; Bonfils, X.; Dumusque, X.; Bouchy, F.; Figueira, P.; Lovis, C.; Melo, C.; Pepe, F.; Queloz, D.; Ségransan, D.; Sousa, S. G.; Udry, S. (7 January 2011). "The HARPS search for southern extrasolar planets. XXV. Results from the metal-poor sample". Astronomy & Astrophysics. 526: A112. arXiv:1011.2094. Bibcode:2011A&A...526A.112S. doi:10.1051/0004-6361/201015494. eISSN 1432-0746. ISSN 0004-6361. S2CID 118675798.
  13. ^ 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.