HD 46375

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HD 46375
Observation data
Epoch J2000      Equinox J2000
Constellation Monoceros
Right ascension 06h 33m 12.62233s[1]
Declination +05° 27′ 46.5283″[1]
Apparent magnitude (V) 7.84
Characteristics
Spectral type K1 IV[2]
Astrometry
Radial velocity (Rv) –1.6[3] km/s
Proper motion (μ) RA: +111.96[1] mas/yr
Dec.: –97.17[1] mas/yr
Parallax (π) 28.72 ± 0.89[1] mas
Distance 114 ± 4 ly
(35 ± 1 pc)
Details
Temperature 3,663 ± 15[4] K
Metallicity [Fe/H] +0.29 ± 0.17[4] dex
Rotational velocity (v sin i) 0.86[5] km/s
Other designations
BD+05°1295, HIP 31246, SAO 114040

HD 46375 is an 8th-magnitude K-type subgiant star located approximately 109 light-years away in the constellation of Monoceros. This star resembles an orange dwarf but has a larger radius and luminosity, indicating that fusion reactions in its core are starting to cease and the star is on its way becoming a red giant. The spectral type of the star is K1 IV. Its advanced evolutionary stage shows that it is considerably older than the Sun.

This star has sometimes been classified as a member of the NGC 2244 star cluster in the Rosette Nebula, but in reality it just happens to lie in the foreground. The distance to the cluster is much greater, about 4500 light-years.

In 2000, a low-mass gas giant was found orbiting the star.

Planetary system[edit]

On March 29, 2000, the planet HD 46375 b with only three quarters the mass of Saturn was discovered by Marcy, Butler, and Vogt in California, together with 79 Ceti b.[6] This planet was discovered using the "wobble method" or radial velocity method, which calculates the rate and shape of the stellar wobble caused by the revolving planet's gravity.

The HD 46375 planetary system[5]
Companion
(in order from star)
Mass Semimajor axis
(AU)
Orbital period
(days)
Eccentricity Inclination Radius
b >0.226 ± 0.019 MJ 0.0398 ± 0.0023 3.023573 ± 0.000065 0.063 ± 0.026

See also[edit]

References[edit]

  1. ^ a b c d e van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, arXiv:0708.1752, Bibcode:2007A&A...474..653V, doi:10.1051/0004-6361:20078357. 
  2. ^ Montes, D. et al. (2001), "Late-type members of young stellar kinematic groups - I. Single stars", Monthly Notices of the Royal Astronomical Society 328 (1): 45–63, arXiv:astro-ph/0106537, Bibcode:2001MNRAS.328...45M, doi:10.1046/j.1365-8711.2001.04781.x. 
  3. ^ Holmberg, J.; Nordstrom, B.; Andersen, J. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics 501 (3): 941–947, arXiv:0811.3982, Bibcode:2009A&A...501..941H, doi:10.1051/0004-6361/200811191. 
  4. ^ a b Rojas-Ayala, Bárbara et al. (April 2012), "Metallicity and Temperature Indicators in M Dwarf K-band Spectra: Testing New and Updated Calibrations with Observations of 133 Solar Neighborhood M Dwarfs", The Astrophysical Journal 748 (2): 93, arXiv:1112.4567, Bibcode:2012ApJ...748...93R, doi:10.1088/0004-637X/748/2/93. 
  5. ^ a b 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. 
  6. ^ Marcy, Geoffrey W. et al. (2000). "Sub-Saturn Planetary Candidates of HD 16141 and HD 46375". The Astrophysical Journal Letters 536 (1): L43–L46. arXiv:astro-ph/0004326. Bibcode:2000ApJ...536L..43M. doi:10.1086/312723. 

External links[edit]

Coordinates: Sky map 06h 33m 12.6237s, +05° 27′ 46.532″