HD 93385

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HD 93385
Observation data
Epoch J2000      Equinox J2000
Constellation Vela
Right ascension 10h 46m 15.11587s[1]
Declination –41° 27′ 51.7235″[1]
Apparent magnitude (V) 7.486[2]
Characteristics
Spectral type G2/G3 V[3]
B−V color index 0.595[4]
Astrometry
Radial velocity (Rv) +47.80 ± 0.61[5] km/s
Proper motion (μ) RA: –48.11[1] mas/yr
Dec.: –53.86[1] mas/yr
Parallax (π) 23.70 ± 0.69[1] mas
Distance 138 ± 4 ly
(42 ± 1 pc)
Details
Mass 1.07[4] M
Radius 1.17[6] R
Luminosity 1.42[6] L
Surface gravity (log g) 4.08 ± 0.11[6] cgs
Temperature 5,823 ± 35[6] K
Metallicity [Fe/H] –0.05 ± 0.03[6] dex
Age 4.13[4] Gyr
Other designations
CD–40 6283, HD 93385, HIP 52676, SAO 222310.[7]

HD 93385 is a star in the southern constellation of Vela. At an apparent visual magnitude of 7.5,[2] it is too faint to be seen with the unaided eye. Parallax measurements made using the Hipparcos satellite show an annual shift of 23.70 milli-arcseconds. This is equivalent to a physical separation of around 138[1] light years from the Sun.

This is an ordinary main sequence star with a stellar classification of G2/G3 V.[3] The physical properties of HD 93385 are similar to those of the Sun; it is slightly larger with 107%[4] of the Sun's mass, 117% of the radius, and 142% of the luminosity. The abundance of elements, other than hydrogen and helium, is nearly the same as in the Sun.[6] It is currently at an unusual low level of surface activity and thus is a candidate Maunder minimum analog.[4]

This star hosts two close-orbiting, super-Earth-like planets.[8] The first has 8.3 times the mass of the Earth and an orbital period of 13.186 days. The second is 10.1 times the Earth's mass with a period of 46.025 days.[9] A physical companion star with an apparent visual magnitude of 12.29 is located at an angular separation of 10.32 arcseconds along a position angle of 288°. It is estimated to have 45% of the mass of the Sun.[10]

References[edit]

  1. ^ a b c d e f 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. ^ a b Høg, E. et al. (March 2000), The Tycho-2 catalogue of the 2.5 million brightest stars, Astronomy and Astrophysics 355: L27–L30, Bibcode:2000A&A...355L..27H, doi:10.1888/0333750888/2862. 
  3. ^ a b Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars 1, Ann Arbor, Michigan: Department of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H. 
  4. ^ a b c d e Lubin, Dan et al. (March 2012), Frequency of Maunder Minimum Events in Solar-type Stars Inferred from Activity and Metallicity Observations, The Astrophysical Journal Letters 747 (2): L32, Bibcode:2012ApJ...747L..32L, doi:10.1088/2041-8205/747/2/L32. 
  5. ^ Valenti, Jeff A.; Fischer, Debra A. (July 2005), Spectroscopic Properties of Cool Stars (SPOCS). I. 1040 F, G, and K Dwarfs from Keck, Lick, and AAT Planet Search Programs, The Astrophysical Journal Supplement Series 159 (1): 141–166, Bibcode:2005ApJS..159..141V, doi:10.1086/430500. 
  6. ^ a b c d e f Ghezzi, L. et al. (September 2010), Stellar Parameters and Metallicities of Stars Hosting Jovian and Neptunian Mass Planets: A Possible Dependence of Planetary Mass on Metallicity, The Astrophysical Journal 720 (2): 1290–1302, arXiv:1007.2681, Bibcode:2010ApJ...720.1290G, doi:10.1088/0004-637X/720/2/1290. 
  7. ^ HD 93385 -- Star, Strasbourg astronomical Data Center (Centre de Données astronomiques de Strasbourg), retrieved 2013-10-07. 
  8. ^ González Hernández, J. I. et al. (April 2013), Searching for the signatures of terrestrial planets in F-, G-type main-sequence stars, Astronomy & Astrophysics 552: A6, arXiv:1301.2109, Bibcode:2013A&A...552A...6G, doi:10.1051/0004-6361/201220165. 
  9. ^ Zolotukhin, Ivan, Catalog, The Extrasolar Planet Encyclopedia, retrieved 2013-10-07. 
  10. ^ Tokovinin, Andrei (February 2011), Low-mass Visual Companions to Nearby G-dwarfs, The Astronomical Journal 141 (2): 52, arXiv:1011.2051, Bibcode:2011AJ....141...52T, doi:10.1088/0004-6256/141/2/52.