Astronomy:HD 33636

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Short description: Binary star system in the constellation Orion
HD 33636 A / B
Observation data
Equinox J2000.0]] (ICRS)
Constellation Orion
Right ascension  05h 11m 46.448s[1]
Declination +04° 24′ 12.73″[1]
Characteristics
Spectral type G0VH-03 / M6V
B−V color index 0.588 ± 0.016 / ?[2]
Astrometry
Proper motion (μ) RA: 169.0 ± 0.3[3] mas/yr
Dec.: -142.3 ± 0.3[3] mas/yr
Parallax (π)35.6 ± 0.2[3] mas
Distance91.6 ± 0.5 ly
(28.1 ± 0.2 pc)
Absolute magnitude (MV)4.77 / ?
Orbit
CompanionHD 33636 B
Period (P)5.797 ± 0.002[3] yr
Semi-major axis (a)14.2 ± 0.2 AU
Inclination (i)4.1 ± 0.1°
Details
Mass1.01 ± 0.02[4]/ ? M
Radius0.97 ± 0.01[4]/ ? R
Luminosity1.08 ± 0.003[4]/ ? L
Surface gravity (log g)4.46 ± 0.02[4]/ ? cgs
Temperature5979 ± 28[4]/ ? K
Age2.5 ± 1.1[4] Gyr
Other designations
BD+04 858, HIP 24205, SAO 74702
Database references
SIMBADdata

HD 33636 is a binary system located approximately 94 light-years away in Orion constellation. The visible member HD 33636 A is a 7th magnitude yellow main-sequence star. It is located at a distance of 91.6 light years from Earth. It has a metallicity of −0.05 ± 0.07.

A companion was discovered in 2002 with a minimum mass of planet size.[2][5] This was ascertained to be a low-mass star in 2007, making it HD 33636 B.[3]

HD 33636 B

HD 33636 B was discovered in 2002 by the Keck telescope in Hawaii.[5] It was independently detected at the Haute-Provence Observatory in France . With this method it showed a minimum mass of 10.58 Jupiter masses, and was initially assumed to be a planet and provisionally labelled "HD 33636 b" (lower-case).[2]

In 2007, Bean et al. used the Hubble Space Telescope (HST) and he found that this body has an inclination as little as 4.1 ± 0.1°, which yielded the true mass of 142 Jupiter masses. This is too high to be a planet. It is now classified as an M-dwarf star of spectral type M6V, "HD 33636 B" (upper-case).

This star takes 2117 days or 5.797 years to orbit at the average distance of 3.27 Astronomical Units (AU).

References

  1. 1.0 1.1 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. http://www.aanda.org/index.php?option=com_article&access=bibcode&Itemid=129&bibcode=2007A%2526A...474..653VFUL.  Vizier catalog entry
  2. 2.0 2.1 2.2 Perrier, C. et al. (2003). "The ELODIE survey for northern extra-solar planets. I. Six new extra-solar planet candidates". Astronomy and Astrophysics 410 (3): 1039–1049. doi:10.1051/0004-6361:20031340. Bibcode2003A&A...410.1039P. 
  3. 3.0 3.1 3.2 3.3 3.4 Bean, Jacob L. et al. (2007). "The Mass of the Candidate Exoplanet Companion to HD 33636 from Hubble Space Telescope Astrometry and High-Precision Radial Velocities". The Astronomical Journal 134 (2): 749–758. doi:10.1086/519956. Bibcode2007AJ....134..749B. 
  4. 4.0 4.1 4.2 4.3 4.4 4.5 Bonfanti, A. et al. (2015). "Revising the ages of planet-hosting stars". Astronomy and Astrophysics 575: A18. doi:10.1051/0004-6361/201424951. Bibcode2015A&A...575A..18B. http://www.aanda.org/articles/aa/full_html/2015/03/aa24951-14/aa24951-14.html. 
  5. 5.0 5.1 Vogt, Steven S. et al. (2002). "Ten Low-Mass Companions from the Keck Precision Velocity Survey". The Astrophysical Journal 568 (1): 352–362. doi:10.1086/338768. Bibcode2002ApJ...568..352V. 

External links