75 Ceti

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
Distance266 ± 10 ly
(81 ± 3 pc)
Details
Mass2.49 (2.22–2.51) M
Radius10.5 (9.5–11.5) R
Luminosity53.7 L
Surface gravity (log g)2.63 ± 0.05 cgs
Temperature4846 ± 18 K
Metallicity+0.00 ± 0.04
Age? years
Other designations
HD 15779, HIP 11791, HR 739
Database references
SIMBADdata
Exoplanet Archivedata
Extrasolar Planets
Encyclopaedia
data

75 Ceti is a G-type giant with at least one planet.[2]

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.[3]

The planet's discoverers consider this planet b "typical" of gas giants.[2] Note that (like many recorded planets) b takes in much more insolation than does Jupiter and, indeed, Earth.[4]

The 75 Ceti planetary system[2]
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. 1.0 1.1 1.2 1.3 1.4 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
  2. 2.0 2.1 2.2 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.
  3. (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 11 日
  4. Square root of luminosity means that an Earth like planet would have to be >7 AU from the star.