HD 11964
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cetus |
| Right ascension | 01h 57m 09.61s[1] |
| Declination | −10° 14′ 32.7″[1] |
| Apparent magnitude (V) | 6.415 |
| Characteristics | |
| Spectral type | G5IV |
| Apparent magnitude (U) | 7.705 |
| Apparent magnitude (B) | 7.255 |
| Apparent magnitude (R) | 5.960 |
| Apparent magnitude (I) | 5.555 |
| Apparent magnitude (J) | 5.023 |
| Apparent magnitude (H) | 4.637 |
| Apparent magnitude (K) | 4.491 |
| U−B color index | 0.450 |
| B−V color index | 0.840 |
| V−R color index | 0.455 |
| R−I color index | 0.405 |
| Variable type | Suspected |
| Astrometry | |
| Radial velocity (Rv) | -6.9 km/s |
| Proper motion (μ) | RA: -366.23 ± 0.49[1] mas/yr Dec.: -242.39 ± 0.49[1] mas/yr |
| Parallax (π) | 30.44 ± 0.60[1] mas |
| Distance | 107 ± 2 ly (32.9 ± 0.6 pc) |
| Absolute magnitude (MV) | +3.76 |
| Details | |
| Mass | 1.12 ± 0.03[2] M☉ |
| Radius | 2.234 ± 0.304[3] R☉ |
| Luminosity | 2.9[2] L☉ |
| Temperature | 5552 K |
| Metallicity [Fe/H] | +0.17 dex |
| Age | 7.02 ± 0.67[2] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| ARICNS | data |
| Extrasolar Planets Encyclopaedia | data |
HD 11964 is a yellow subgiant star approximately 107 light-years away in the constellation of Cetus. The star is more massive and luminous than our Sun and is barely visible to the naked eye. A wide binary companion star was discovered in 2000.[4] Two extrasolar planets have been confirmed to orbit the star.
Planetary system
In August 2005, two planets were discovered orbiting the star, the innermost like Neptune and another like Jupiter orbiting at 3.34 AU. However, the second planet (HD 11964 b) was not confirmed until May 2007. In September 2007, P.C. Gregory claimed that there was a third planet in the system on the basis of Bayesian analysis of the radial velocity data. The planet was claimed to have a mass similar to that of Saturn and located in a 360-day orbit. Gregory cautioned that the close match between the period of this planet to being exactly a year meant that the radial velocity variations may have been caused by insufficient correction for the motion of the Earth in orbit around the Sun.[5] The planet was not detected in re-reduced data in an analysis published in the Astrophysical Journal in 2009.[6]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| c | ≥0.11 MJ | 0.229 | 37.82 | 0.15 | — | — |
| b | ≥0.61 ± 0.1 MJ | 3.34 ± 0.4 | 2110 ± 70 | 0.06 ± 0.2 | — | — |
See also
References
- 1 2 3 4 5 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. Vizier catalog entry
- 1 2 3 Ghezzi, L.; et al. (December 2010), "Metallicities of Planet-hosting Stars: A Sample of Giants and Subgiants", The Astrophysical Journal 725 (1): 721–733, arXiv:1008.3539, Bibcode:2010ApJ...725..721G, doi:10.1088/0004-637X/725/1/721.
- ↑ van Belle, Gerard T.; von Braun, Kaspar (2009). "Directly Determined Linear Radii and Effective Temperatures of Exoplanet Host Stars". The Astrophysical Journal 694 (2): 1085–1098. arXiv:0901.1206. Bibcode:2009ApJ...694.1085V. doi:10.1088/0004-637X/694/2/1085.
- ↑ Allen; et al. (2000). "Wide binaries among high-velocity and metal-poor stars". Astronomy and Astrophysics 356 (2): 529–540. Bibcode:2000A&A...356..529A.
- ↑ Gregory, P.C. (2007). "A Bayesian periodogram finds evidence for three planets in HD 11964". MNRAS 381 (4): 1607–1616. arXiv:0709.0970. Bibcode:2007MNRAS.381.1607G. doi:10.1111/j.1365-2966.2007.12361.x.
- 1 2 Wright, J. T.; et al. (2009). "Ten New and Updated Multi-planet Systems, and a Survey of Exoplanetary Systems". The Astrophysical Journal 693 (2): 1084–1099. arXiv:0812.1582. Bibcode:2009ApJ...693.1084W. doi:10.1088/0004-637X/693/2/1084.
External links
- Extrasolar Planet Interactions by Rory Barnes & Richard Greenberg, Lunar and Planetary Lab, University of Arizona
Coordinates: 
01h 57m 09.6064s, −10° 14′ 32.739″
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