Langbahn Team – Weltmeisterschaft

HD 30177

HD 30177
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Dorado[1]
Right ascension 04h 41m 54.374s[2]
Declination −58° 01′ 14.73″[2]
Apparent magnitude (V) 8.41[1]
Characteristics
Evolutionary stage main sequence[3]
Spectral type G8V[4]
B−V color index 0.773±0.015[1]
Astrometry
Radial velocity (Rv)62.697±0.0013[5] km/s
Proper motion (μ) RA: 66.303±0.023 mas/yr[2]
Dec.: −11.795±0.024 mas/yr[2]
Parallax (π)18.0190 ± 0.0195 mas[2]
Distance181.0 ± 0.2 ly
(55.50 ± 0.06 pc)
Absolute magnitude (MV)4.72±0.09[3]
Details[6]
Mass1.053±0.023 M☉
Radius1.019±0.034 R☉
Luminosity1.04±0.01[7] L☉
Surface gravity (log g)4.417±0.034 cgs
Temperature5,607±47 K
Metallicity [Fe/H]0.39±0.05 dex
Rotation~45 d
Rotational velocity (v sin i)2.96±0.50[8] km/s
Age4.8±1.5 Gyr[7]
2.525±1.954[6] Gyr
Other designations
CD−58°984, HD 30177, HIP 21850, SAO 233633, 2MASS J04415438-5801146[9]
Database references
SIMBADdata

HD 30177 is a single star with a pair of orbiting exoplanets in the southern constellation Dorado. Based on parallax measurements, it is located at a distance of 181 light years from the Sun. It has an absolute magnitude of 4.72,[3] but at that distance the star is too faint to be viewed by the naked eye with an apparent visual magnitude of 8.41.[1] The star is drifting further away with a radial velocity of 62.7 km/s.[5]

The spectrum of HD 30177 matches a late G-type main-sequence star with a stellar classification of G8V.[4] It is a yellow dwarf with a mass and radius similar to the Sun that is fusing hydrogen in its core. The chromosphere shows a negligible level of magnetic activity.[3] The abundance of iron, an indicator of the star's metallicity, is more than double the Sun's. It is radiating a similar luminosity to the Sun from its photosphere at an effective temperature of 5,607 K.[6]

A 2024 multiplicity survey, using astrometry from the Gaia spacecraft, identified a proper motion companion to HD 30177. This co-moving companion is a red dwarf star, around 10% the mass of the Sun, is located at 780" from HD 30177 with a position angle of 188°. The angular distance translates to an observed separation of 43,300 astronomical units.[10]

Planetary system

The Anglo-Australian Planet Search team announced the discovery of HD 30177 b, which has a minimum mass 8 times that of Jupiter, on June 13, 2002. The scientific paper describing the discovery was published in The Astrophysical Journal in 2003.[11][3] A second massive gas giant planet was later discovered in an approximately 32 year orbit.[12] In 2022, the inclination and estimated mass of both planets were measured via astrometry.[13]

The HD 30177 planetary system[13]
Companion
(in order from star) 		Mass Semimajor axis
(AU) 		Orbital period
(years) 		Eccentricity Inclination Radius
b 8.403+1.241
−0.489 MJ 		3.604+0.135
−0.147 		6.884+0.014
−0.012 		0.207+0.012
−0.017 		85.393+14.354
−18.742° 		—
c 6.150+1.308
−0.341 MJ 		10.258+0.535
−0.480 		33.088+1.596
−1.207 		0.039+0.005
−0.013 		98.016+16.025
−24.235° 		—

See also

References

  1. ^ a b c d 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. ^ a b c d e Tinney, C. G.; et al. (2003). "Four New Planets Orbiting Metal-enriched Stars". The Astrophysical Journal. 587 (1): 423–428. arXiv:astro-ph/0207128. Bibcode:2003ApJ...587..423T. doi:10.1086/368068.
  4. ^ a b Houk, Nancy; Cowley, Anne P. (1975). University of Michigan Catalogue of Two-Dimensional Spectral Types for the HD Stars. Declinations −90° to −53°. Vol. 1. Department of Astronomy, University of Michigan. Bibcode:1975mcts.book.....H. ISBN 978-0-8357-0331-4.
  5. ^ 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.
  6. ^ a b c Barbato, D.; et al. (August 2018). "Exploring the realm of scaled solar system analogues with HARPS". Astronomy & Astrophysics. 615: 21. arXiv:1804.08329. Bibcode:2018A&A...615A.175B. doi:10.1051/0004-6361/201832791. S2CID 119099721. A175.
  7. ^ a b Bonfanti, A.; et al. (2015). "Revising the ages of planet-hosting stars". Astronomy and Astrophysics. 575. A18. arXiv:1411.4302. Bibcode:2015A&A...575A..18B. doi:10.1051/0004-6361/201424951.
  8. ^ Butler, R. P.; et al. (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.
  9. ^ "HD 30177". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-08-22.
  10. ^ González-Payo, J.; Caballero, J. A.; Gorgas, J.; Cortés-Contreras, M.; Gálvez-Ortiz, M.-C.; Cifuentes, C. (2024-07-29). "Multiplicity of stars with planets in the solar neighbourhood". arXiv:2407.20138 [astro-ph.SR].
  11. ^ Tinney, Chris (2007-09-07). "AAPS Discovered Planets". Anglo-Australian Planet Search. University of New South Wales. Retrieved 2018-04-17.
  12. ^ Wittenmyer, Robert A.; et al. (2017). "The Anglo-Australian Planet Search. XXV. A Candidate Massive Saturn Analog Orbiting HD 30177". The Astronomical Journal. 153 (4). 167. arXiv:1612.02072. Bibcode:2017AJ....153..167W. doi:10.3847/1538-3881/aa5f17.
  13. ^ a b Feng, Fabo; Butler, R. Paul; et al. (August 2022). "3D Selection of 167 Substellar Companions to Nearby Stars". The Astrophysical Journal Supplement Series. 262 (21): 21. arXiv:2208.12720. Bibcode:2022ApJS..262...21F. doi:10.3847/1538-4365/ac7e57. S2CID 251864022.


Quelle: https://en.wikipedia.org/wiki/HD_30177