Gliese 651
From Wikipedia, the free encyclopedia
(Redirected from HD 154345)
| Observation data Epoch J2000.0 Equinox J2000.0 |
|
|---|---|
| Constellation | Hercules |
| Right ascension | 17h 02m 36.40s |
| Declination | +47° 04′ 54.77″ |
| Apparent magnitude (V) | +6.74 |
| Characteristics | |
| Spectral type | G8V |
| U−B color index | 0.27 |
| B−V color index | 0.73 |
| Variable type | none |
| Astrometry | |
| Radial velocity (Rv) | -46.2 km/s |
| Proper motion (μ) | RA: 123.55 mas/yr Dec.: 854.71 mas/yr |
| Parallax (π) | 55.37 ± 0.55 mas |
| Distance | 58.91 ± 0.59 ly (18.06 ± 0.18 pc) |
| Absolute magnitude (MV) | +5.46 |
| Details | |
| Mass | 0.88 M☉ |
| Luminosity | 0.568 L☉ |
| Temperature | 5468 ± 44 K |
| Metallicity | -0.105 ± 0.03 |
| Rotation | 27.8 ± 1.7 days[1] |
| Age | 4.92 ± 4.48 × 109 years |
| Other designations | |
|
HD 154345, BD+47º2420, GC 23011, GCRV 9834, GJ 651, HIP 83389, SAO 46452
|
|
Gliese 651 is a G-type dwarf star located in northern Hercules. It is not visible to the naked eye since this star is below +6.50 magnitude, but using binoculars it is an easy target.
[edit] Planetary system
In 2006, a long-period, wide-orbiting planet was observed by radial velocity, and published in May 2007, gaining the designation Gliese 651 b.[2] The complete observation of its nine-year orbit rules out any interior planets of minimum mass (m sini) greater than 0.3 Jupiter. The system's habitable zone is centered at .754 AU and is narrower than Sol's.[3] Assuming that the system is oriented edge-on to Earth (inclination ~90, so that the real mass of the planet is about equal to Jupiter's), Gliese 651 b does not come close enough to the habitable zone to disrupt the orbits of potential Earth-like planets in the system.
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (years) |
Eccentricity |
|---|---|---|---|---|
| b | >0.947 ± 0.090 MJ | 4.19 ± 0.26 | 9.15 ± 0.26 | 0.044 ± 0.046 |
[edit] References
- ^ Simpson, E. K. et al. (November 2010), "Rotation periods of exoplanet host stars", Monthly Notices of the Royal Astronomical Society 408 (3): 1666–1679, Bibcode 2010MNRAS.408.1666S, doi:10.1111/j.1365-2966.2010.17230.x
- ^ Wright, J. T. et al (2007). "Four New Exoplanets and Hints of Additional Substellar Companions to Exoplanet Host Stars". The Astrophysical Journal 657 (1): 533–545. arXiv:astro-ph/0611658. Bibcode 2007ApJ...657..533W. doi:10.1086/510553. http://www.iop.org/EJ/article/0004-637X/657/1/533/65907.html.
- ^ Square root of stellar luminosity.
- ^ Wright, J. T. et al (2008). "The Jupiter Twin HD 154345b". The Astrophysical Journal Letters 683 (1): L63–L66. arXiv:0802.1731. Bibcode 2008ApJ...683L..63W. doi:10.1086/587461. http://iopscience.iop.org/1538-4357/683/1/L63/fulltext/.
[edit] External links
Coordinates: 
17h 02m 36.40s, +47° 04′ 54.77″
|
|||||||||||||||||||||||||||||||||||||||||||
 |
This main sequence star-related article is a stub. You can help Wikipedia by expanding it. |
