75 Ceti
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Cetus |
| Right ascension | 02h 32m 09.422s[1] |
| Declination | −01° 02′ 05.62″[1] |
| Apparent magnitude (V) | +5.36 |
| Characteristics | |
| Spectral type | G3 III |
| Astrometry | |
| Proper motion (μ) | RA: -24.72 ± 0.46[1] mas/yr Dec.: -32.08 ± 0.40[1] mas/yr |
| Parallax (π) | 12.28 ± 0.45[1] mas |
| Distance | 266 ± 10 ly (81 ± 3 pc) |
| Absolute magnitude (MV) | 0.808[2] |
| Details | |
| Mass | 2.16[2] M☉ |
| Radius | 10.5 (9.5–11.5) R☉ |
| Luminosity | 53.7 L☉ |
| Surface gravity (log g) | 2.75[2] cgs |
| Temperature | 4,784[2] K |
| Metallicity | −0.05[2] |
| Other designations | |
| Database references | |
| SIMBAD | data |
| Exoplanet Archive | data |
| Extrasolar Planets Encyclopaedia | data |
75 Ceti is a G-type giant with at least one planet.[3]
In Chinese, 天囷 (Tiān Qūn), meaning Circular Celestial Granary, refers to an asterism consisting of α Ceti, κ1 Ceti, λ Ceti, μ Ceti, ξ1 Ceti, ξ2 Ceti, ν Ceti, γ Ceti, δ Ceti, 75 Ceti, 70 Ceti, 63 Ceti and 66 Ceti. Consequently, 75 Ceti itself is known as the Tenth Star of Circular Celestial Granary.[4]
The planet's discoverers consider this planet b "typical" of gas giants.[3] Note that (like many recorded planets) b takes in much more insolation than does Jupiter and, indeed, Earth.[5]
| Companion (in order from star) |
Mass | Semimajor axis (AU) |
Orbital period (days) |
Eccentricity | Inclination | Radius |
|---|---|---|---|---|---|---|
| b | >3 MJ | 2.1 | 691.9 ± 3.6 | 0.117 ± 0.048 | — | — |
There may be additional periodic factors in the data, corresponding to m sin i of around 0.4 MJ and 1 MJ, at distances of ∼0.9 AU and ∼4 AU. If these are confirmed, they are more irradiated than Earth as well.
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 4 5 Liu, Y. J.; et al. (2007), "The abundances of nearby red clump giants", Monthly Notices of the Royal Astronomical Society, 382 (2): 553–66, Bibcode:2007MNRAS.382..553L, doi:10.1111/j.1365-2966.2007.11852.x.
- 1 2 3 Sato, Bun'ei; et al. (2012). "Substellar Companions to Seven Evolved Intermediate-Mass Stars". Publications of the Astronomical Society of Japan. 64 (6). 135. arXiv:1207.3141. Bibcode:2012PASJ...64..135S. doi:10.1093/pasj/64.6.135.
- ↑ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 11 日
- ↑ Square root of luminosity means that an Earth like planet would have to be >7 AU from the star.