HD_154857

HD 154857

HD 154857

Star in the constellation of Ara

HD 154857 is a star with two exoplanetary companions in the southern constellation of Ara. It is too dim to be visible with the naked eye having an apparent visual magnitude of 7.25.[2] The star is located at a distance of 207 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +28 km/s.[1]

Quick Facts Observation data Epoch J2000 Equinox J2000, Constellation ...

This is a G-type star with a stellar classification of G5IV-V.[3] The absolute magnitude of this star is two magnitudes above the main sequence, which suggests that the star is evolving toward the subgiant stage.[3] It is a metal-poor thin disk star[9] approximately six billion years old and is chromopherically quiet although not in a Maunder Minimum state.[4] The star is larger, more massive, and more luminous than the Sun. It is spinning with a projected rotational velocity of 1.4 km/s.[7]

Planetary system

The discovery of one confirmed and one unconfirmed Jovian exoplanet was reported in 2004[3] and 2007[10] respectively. The former planet HD 154857 b has mass >1.8 times that of Jupiter. It orbits the star 20% further than Earth-Sun distance, taking 409 days with 47% eccentricity. The additional object (HD 154857 c) was confirmed as a planetary companion in January 2014.[5]

More information Companion (in order from star), Mass ...

See also

References

  1. [1]
    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.
  2. [2]
    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. [3]
    McCarthy, Chris; et al. (2004). "Multiple Companions to HD 154857 and HD 160691". The Astrophysical Journal. 617 (1): 575–579. arXiv:astro-ph/0409335. Bibcode:2004ApJ...617..575M. doi:10.1086/425214. S2CID 119446133.
  4. [4]
    Bonfanti, A.; Ortolani, S.; Nascimbeni, V. (2016). "Age consistency between exoplanet hosts and field stars". Astronomy & Astrophysics. 585: 14. arXiv:1511.01744. Bibcode:2016A&A...585A...5B. doi:10.1051/0004-6361/201527297. S2CID 53971692. A5.
  5. [5]
    Wittenmyer, Robert A.; et al. (March 2014). "The Anglo-Australian Planet Search. XXIII. Two New Jupiter Analogs". The Astrophysical Journal. 783 (2): 9. arXiv:1401.5525. Bibcode:2014ApJ...783..103W. doi:10.1088/0004-637X/783/2/103. S2CID 14082923. 103.
  6. [6]
    Sousa, S. G.; et al. (November 2018). "SWEET-Cat updated. New homogenous spectroscopic parameters". Astronomy & Astrophysics. 620: 13. arXiv:1810.08108. Bibcode:2018A&A...620A..58S. doi:10.1051/0004-6361/201833350. S2CID 119374557. A58.
  7. [7]
    Butler, R. P.; et al. (December 2006). "Catalog of Nearby Exoplanets". The Astrophysical Journal. 646 (1): 505–522. arXiv:astro-ph/0607493. Bibcode:2006ApJ...646..505B. doi:10.1086/504701. S2CID 119067572.
  8. [8]
    "HD 154857". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2021-10-10.
  9. [9]
    Gonzalez, Guillermo (October 2009). "Stars with planets and the thick disc". Monthly Notices of the Royal Astronomical Society: Letters. 399 (1): L103–L107. Bibcode:2009MNRAS.399L.103G. doi:10.1111/j.1745-3933.2009.00734.x.
  10. [10]
    O'Toole, Simon J.; et al. (2007). "New Planets around Three G Dwarfs". The Astrophysical Journal. 660 (2): 1636–1641. arXiv:astro-ph/0702213. Bibcode:2007ApJ...660.1636O. doi:10.1086/513563. S2CID 118958847.
Share this article:

This article uses material from the Wikipedia article HD_154857, and is written by contributors. Text is available under a CC BY-SA 4.0 International License; additional terms may apply. Images, videos and audio are available under their respective licenses.