HD_33636
HD 33636
Binary star system in the constellation Orion
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.
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| 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 mas[3] |
| Distance | 91.6 ± 0.5 ly (28.1 ± 0.2 pc) |
| Absolute magnitude (MV) | 4.77 / ? |
| Orbit | |
| Companion | HD 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 | |
| Mass | 1.01 ± 0.02[4]/ ? M☉ |
| Radius | 0.97 ± 0.01[4]/ ? R☉ |
| Luminosity | 1.08 ± 0.003[4]/ ? L☉ |
| Surface gravity (log g) | 4.46 ± 0.02[4]/ ? cgs |
| Temperature | 5979 ± 28[4]/ ? K |
| Age | 2.5 ± 1.1[4] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
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 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).
- van Leeuwen, F. (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. S2CID 18759600. Vizier catalog entry
- 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. arXiv:astro-ph/0308281. Bibcode:2003A&A...410.1039P. doi:10.1051/0004-6361:20031340. S2CID 6946291.
- 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. arXiv:0705.1861. Bibcode:2007AJ....134..749B. doi:10.1086/519956. S2CID 119599833.
- 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. S2CID 54555839.
- Vogt, Steven S.; et al. (2002). "Ten Low-Mass Companions from the Keck Precision Velocity Survey". The Astrophysical Journal. 568 (1): 352–362. arXiv:astro-ph/0110378. Bibcode:2002ApJ...568..352V. doi:10.1086/338768. S2CID 2272917.
- "G 97-25 -- High Proper Motion Star". SIMBAD. Retrieved December 21, 2007.
- "HD 33636b -- Star". SIMBAD. Retrieved December 21, 2007.
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