75 Ceti

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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)
Details
Mass 2.49 (2.22–2.51) M
Radius 10.5 (9.5–11.5) R
Luminosity 53.7 L
Surface gravity (log g) 2.63 ± 0.05 cgs
Temperature 4846 ± 18 K
Metallicity +0.00 ± 0.04
Age ? years
Other designations
HD 15779, HIP 11791, HR 739
Database references
SIMBAD data
Exoplanet Archive data
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[edit]

  1. ^ a b c d e 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. ^ a b c 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.