Langbahn Team – Weltmeisterschaft

HD 181433

HD 181433
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Pavo[1]
Right ascension 19h 25m 09.567s[2]
Declination −66° 28′ 07.68″[2]
Apparent magnitude (V) 8.40[1]
Characteristics
Spectral type K3III-IV[3]
B−V color index 1.006±0.045[1]
Astrometry
Radial velocity (Rv)+40.144±0.0003[4] km/s
Proper motion (μ) RA: –230.723 mas/yr[2]
Dec.: 235.806 mas/yr[2]
Parallax (π)37.0511 ± 0.0211 mas[2]
Distance88.03 ± 0.05 ly
(26.99 ± 0.02 pc)
Absolute magnitude (MV)6.26[1]
Details
Mass0.84±0.02[5] M
Radius0.80±0.02[5] R
Luminosity0.34±0.01[5] L
Surface gravity (log g)4.55±0.02[5] cgs
Temperature4,909±20[5] K
Metallicity [Fe/H]0.33[6] dex
Rotational velocity (v sin i)1.588±0.072[7] km/s
Age6.7±1.8 Gyr[6]
7.4±3.4[5] Gyr
Other designations
CD−66° 2307, GJ 756.1, HD 181433, HIP 95467, SAO 254563, PPM 363979, LTT 7669[8]
Database references
SIMBADdata
Exoplanet Archivedata

HD 181433 is a star with a system of orbiting exoplanets located in the southern constellation of Pavo (the Peacock). With an apparent visual magnitude of 8.40,[1] it is too faint to be visible to the naked eye. It lies at a distance of 88 light years from the Sun based on parallax measurements, and is drifting further away with a radial velocity of +40 km/s.[4] The system shows a high proper motion, traversing the celestial sphere at an angular rate of 0.340 arcsec yr−1.[9]

This K-type star has a stellar classification of K3III-IV, which presents it as an evolved star with mixed traits of a red giant and a subgiant. G. Campanella and associates list a class of K3IV.[10] These are inconsistent with the fact that its luminosity is only 0.34 times that of the Sun.[11][5] Its entry in the Hipparcos catalogue lists a spectral type of K5V,[12] classifying it as an ordinary K-type main-sequence star, an orange dwarf.

HD 181433 is an older star with age estimates of around 7 billion years.[7][5] It is smaller than the Sun, with 84% of the Sun's mass and 80% of the radius.[5] This star is spinning with a projected rotational velocity of 1.6 km/s.[7] The effective temperature of the stellar atmosphere is 4,909 K.[5]

Planetary system

Orbiting the star are three planets, whose discovery was announced in 2008;[13] the discovery paper was published in 2009.[11] The inner planet has a mass at least 7.5 times that of Earth, and is termed a super-Earth (this classification is based solely on the mass of the planet and should not be taken to imply that the planet could support Earthlike conditions). The middle planet and the outer planet are gas giants. The orbital periods for three planets are 9.3743 days for a 7.56 ME planet, 962 days for a 0.64 MJ planet, and 2172 days for a 0.54 MJ planet.[11] This solution is unstable, more data are required to constrain the orbital position of planet d.[14]

The HD 181433 planetary system[11]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b ≥0.0238 MJ 0.080 9.3743 ± 0.0019 0.396 ± 0.062
c ≥0.64 MJ 1.76 962 ± 15 0.28 ± 0.02
d ≥0.54 MJ 3.00 2,172 ± 158 0.48 ± 0.05

See also

References

  1. ^ a b c d e 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.
  2. ^ 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.
  3. ^ Gray, R. O.; et al. (2006). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc-The Southern Sample". The Astronomical Journal. 132 (1): 161–170. arXiv:astro-ph/0603770. Bibcode:2006AJ....132..161G. doi:10.1086/504637. S2CID 250741593.
  4. ^ a b Soubiran, C.; et al. (2018). "Gaia Data Release 2. The catalogue of radial velocity standard stars". Astronomy and Astrophysics. 616: A7. arXiv:1804.09370. Bibcode:2018A&A...616A...7S. doi:10.1051/0004-6361/201832795. S2CID 52952408.
  5. ^ a b c d e f g h i j Bonfanti, A.; et al. (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.
  6. ^ a b Trevisan, M.; et al. (November 2011). "Analysis of old very metal rich stars in the solar neighbourhood". Astronomy & Astrophysics. 535: A42. arXiv:1109.6304. Bibcode:2011A&A...535A..42T. doi:10.1051/0004-6361/201016056. S2CID 49565866.. See table 13.
  7. ^ a b c Soto, M. G.; Jenkins, J. S. (July 2018). "Spectroscopic Parameters and atmosphEric ChemIstriEs of Stars (SPECIES). I. Code description and dwarf stars catalogue". Astronomy & Astrophysics. 615: 28. arXiv:1801.09698. Bibcode:2018A&A...615A..76S. doi:10.1051/0004-6361/201731533. A76.
  8. ^ "HD 181433". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2024-01-15.
  9. ^ Luyten, W. J. (June 1995). "NLTT Catalogue (Luyten, 1979)". VizieR Online Data Catalog. Bibcode:1995yCat.1098....0L.
  10. ^ Campanella, Giammarco; et al. (August 2013). "Possible scenarios for eccentricity evolution in the extrasolar planetary system HD 181433". Monthly Notices of the Royal Astronomical Society. 433 (4): 3190–3207. arXiv:1305.7508. Bibcode:2013MNRAS.433.3190C. doi:10.1093/mnras/stt959.
  11. ^ a b c d Bouchy, François; et al. (2009). "The HARPS Search for Southern Extra-solar Planets. XVII. Super-Earth and Neptune-mass Planets in Multiple Planet Systems HD 47186 and HD 181433". Astronomy and Astrophysics. 496 (2): 527–31. arXiv:0812.1608. Bibcode:2009A&A...496..527B. doi:10.1051/0004-6361:200810669. S2CID 117778593.
  12. ^ ESA (1997). "HIP 95152". The Hipparcos and Tycho Catalogues: The Hipparcos Main Catalogue. Retrieved 2008-10-02.
  13. ^ "Astronomers find batch of "Super Earths"". BT Yahoo.com. Archived from the original on 2008-06-17. Retrieved 2008-06-16.
  14. ^ Campanella, G. (2011). "Treating dynamical stability as an observable: a 5:2 MMR configuration for the extrasolar system HD 181433". Monthly Notices of the Royal Astronomical Society. 418 (2): 1028–1038. arXiv:1108.0360. Bibcode:2011MNRAS.418.1028C. doi:10.1111/j.1365-2966.2011.19553.x. S2CID 117708552.