75 Ceti

Last updated
75 Ceti
Observation data
Epoch J2000.0       Equinox J2000.0
Constellation Cetus
Right ascension 02h 32m 09.42241s [1]
Declination −01° 02′ 05.6166″ [1]
Apparent magnitude  (V)+5.36 [2]
Characteristics
Spectral type K1 III [3]
B−V color index +1.004±0.002 [2]
Astrometry
Radial velocity (Rv)−6.34±0.13 [1]  km/s
Proper motion (μ)RA: −23.268  mas/yr [1]
Dec.: −30.987  mas/yr [1]
Parallax (π)12.1717 ± 0.0962  mas [1]
Distance 268 ± 2  ly
(82.2 ± 0.6  pc)
Absolute magnitude  (MV)0.808 [4]
Details
Mass 1.85±0.05 [5]   M☉
Radius 10.38+0.15
−0.26 [6]   R☉
Luminosity 56.1±0.6 [7]   L☉
Surface gravity (log g)2.67±0.04 [5]   cgs
Temperature 4,846+163
−128 [7]   K
Metallicity [Fe/H]0.00±0.06 [5]   dex
Age 1.41±0.01 [5]   Gyr
Other designations
75 Cet, BD–01°353, GC  3043, HD  15779, HIP  11791, HR  739, SAO  129959 [8]
Database references
SIMBAD data
Exoplanet Archive data
Extrasolar Planets
Encyclopaedia 		data

75 Ceti is a single [9] star in the equatorial constellation of Cetus with at least two planets. [6] It is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of +5.36. [2] The star is located 268 light-years (82 parsecs ) distant from the Sun, based on parallax, but is drifting closer with a radial velocity of −6 km/s. [1]

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. [10]

This is an aging giant star with a stellar classification of K1 III, [3] having exhausted the supply of hydrogen at its core and expanded to 10.6 [7] times the Sun's radius, or 0.05  AU. It is a red clump giant, [5] which indicates it is on the horizontal branch and is generating energy through helium fusion at the core. The star is 1.4 [5]  billion years old with 1.9 [5] times the Sun's mass. It is radiating 56 [7] times the luminosity of the Sun from its swollen photosphere at an effective temperature of 4,846 K. [7]

Planetary system

A planetary companion was discovered by Doppler measurements at the Okayama Astrophysical Observatory, and announced in 2012. The planet's discoverers consider the planet, designated 75 Ceti b, to be "typical" of gas giants. [11] Note that (like many recorded planets) b takes in much more insolation than does Jupiter and, indeed, Earth. [12]

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, where i is the orbital inclination and m is the planet's actual mass. [11] In 2023, the presence of a second, Jupiter-mass planet orbiting at 4 AU (75 Ceti c) was confirmed, which is more irradiated than Earth as well. The shorter period signal corresponding to a possible planet at 0.9 AU was found to be an alias of the true period of planet c. [6]

The 75 Ceti planetary system [6]
Companion
(in order from star)		 Mass Semimajor axis
(AU)		 Orbital period
(days)		 Eccentricity Inclination Radius
b≥2.479+0.074
−0.090  MJ 		1.912+0.002
−0.003		696.62+1.33
−1.69		0.093+0.026
−0.042		——
c≥0.912+0.088
−0.143  MJ 		3.929+0.058
−0.052		2051.62+45.98
−40.47		0.023+0.191
−0.003		——

Related Research Articles

79 Ceti, also known as HD 16141, is a binary star system located 123 light-years from the Sun in the southern constellation of Cetus. It has an apparent visual magnitude of +6.83, which puts it below the normal limit for visibility with the average naked eye. The star is drifting closer to the Earth with a heliocentric radial velocity of −51 km/s.

Omega Serpentis is a solitary star within the Serpens Caput part of the equatorial constellation of Serpens. It is visible to the naked eye with an apparent visual magnitude of +5.22. Based upon an annual parallax shift of 11.93 mas as seen from Earth, it is located about 273 light years from the Sun. At that distance, its visual magnitude is diminished by an extinction factor of 0.19 due to interstellar dust. It is a member of the Ursa Major Stream, lying among the outer parts, or corona, of this moving group of stars that roughly follow a common heading through space.

14 Andromedae, abbreviated 14 And, also named Veritate, is a single, orange-hued giant star situated approximately 247 light-years away in the northern constellation of Andromeda. It is dimly visible to the naked eye with an apparent visual magnitude of 5.22. The star is moving closer to the Earth with a heliocentric radial velocity of −60 km/s. In 2008 an extrasolar planet was discovered to be orbiting the star.

44 Aquarii is a single star located 336 light years away from the Sun in the equatorial constellation of Aquarius. 44 Aquarii is its Flamsteed designation. It is visible to the naked eye as a dim, yellow-hued star with an apparent visual magnitude of 5.75. This body is moving away from the Earth with a heliocentric radial velocity of +7.4 km/s.

38 Aurigae is a star located 236 light years away from the Sun in the northern constellation of Auriga. It is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 6.08. The star is moving further from the Earth with a heliocentric radial velocity of +34 km/s, and it has a relatively high proper motion, traversing the celestial sphere at the rate of 0.181 arc seconds per annum. It is a probable member of the Hercules stream.

Gliese 412 is a pair of stars that share a common proper motion through space and are thought to form a binary star system. The pair have an angular separation of 31.4″ at a position angle of 126.1°. They are located 15.8 light-years distant from the Sun in the constellation Ursa Major. Both components are relatively dim red dwarf stars.

HD 104985, formally named Tonatiuh, is a solitary star with a exoplanetary companion in the northern constellation of Camelopardalis. The companion is designated HD 104985 b and named Meztli. This star has an apparent visual magnitude of 5.78 and thus is dimly visible to the naked eye under favorable seeing conditions. It is located at a distance of approximately 329 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −20 km/s.

41 Lyncis, also designated HD 81688 and named Intercrus, is a fifth-magnitude star located in the northern constellation of Ursa Major. An extrasolar planet is thought to be orbiting the star.

81 Ceti is a star located approximately 331 light years away from the Sun in the equatorial constellation of Cetus. 81 Ceti is the Flamsteed designation for this object. It is visible to the naked eye as a dim, yellow-hued point of light with an apparent visual magnitude of 5.65. The star is drifting further away from the Earth with a heliocentric radial velocity of +9 km/s.

6 Lyncis is a star in the northern constellation of Lynx, located approximately 179 light years from Earth. It is visible to the naked eye as a dim, orange-hued star with an apparent visual magnitude of 5.86. This object is moving away from the Earth with a heliocentric radial velocity of +40 km/s. It has a relatively high proper motion, traversing the celestial sphere at the rate of 0.341 arc seconds per annum.

27 Hydrae is a member of a triple star system system in the equatorial constellation of Hydra, located 222 light years away from the Sun. It is visible to the naked eye as a faint, orange-hued star with a combined apparent visual magnitude of 4.82. The system is moving further from the Earth with a heliocentric radial velocity of +25.6 km/s.

HD 203857 is a double star in the constellation Cygnus. It is near the lower limit of visibility to the naked eye, having a combined apparent visual magnitude of 6.46. The distance to the primary component is approsimatly 1,230 light years based on parallax, and it has an absolute magnitude of −0.75. The star is drifting closer to the Sun with a radial velocity of −6.3 km/s. It has a stellar classification of K5 and is known to be evolved. The star likely hosts an extrasolar planet, though yet unconfirmed.

<span class="mw-page-title-main">Nu Ceti</span> Binary star system in the constellation Cetus

ν Ceti, Latinized as Nu Ceti, is a binary star system in the equatorial constellation of Cetus. It is visible to the naked eye as a faint point of light with a combined apparent visual magnitude of 4.86. The system is located approximately 340 light years distant from the Sun, based on parallax, and is drifting further away with a radial velocity of 4.8 km/s. Nu Ceti is believed to be part of the Ursa Major stream of co-moving stars.

Xi<sup>1</sup> Ceti Star in the constellation Cetus

Xi1 Ceti , Latinized from ξ1 Ceti, is a binary star system located in the equatorial constellation of Cetus. It is visible to the naked eye with a combined apparent visual magnitude of +4.36. The distance to this system is approximately 340 light years based on parallax measurements, and it is drifting closer to the Sun with a radial velocity of −4 km/s. The proximity of the star to the ecliptic means it is subject to lunar occultations.

Xi2 Ceti, Latinized from ξ2 Ceti, is a star located in the equatorial constellation of Cetus. It is visible to the naked eye with an apparent visual magnitude of +4.3. This star is located at a distance of approximately 197 light years from the Sun based on parallax, and is drifting further away with a radial velocity of 12 km/s. It made its closest approach some 2.7 million years ago at a distance of around 128 light-years.

15 Cygni is a single star in the northern constellation Cygnus. With an apparent visual magnitude of 4.90, it is a faint star but visible to the naked eye. The distance to 15 Cygni can be estimated from its annual parallax shift of 11.0 mas, which yields a separation of some 296 light years. It is moving closer to the Sun with a heliocentric radial velocity of −23.6 km/s.

HD 5608 is an orange-hued star in the northern constellation of Andromeda with one known planet, HD 5608 b. It is a dim star near the lower limit of visibility to the naked eye, having an apparent visual magnitude of +5.98. The distance to HD 5608, as estimated from an annual parallax shift of 17.18 mas, is 190 light years. It is moving closer to the Earth with a heliocentric radial velocity of −23 km/s, and is expected to make its closest approach in 1.285 million years when it comes to within 124 light-years.

HD 100655 is a star in the zodiac constellation of Leo, located 449 light years away from the Sun. It has an apparent visual magnitude of +6.45, which makes it a challenge to see with the naked eye under ideal viewing conditions. The star is moving closer to the Earth with a heliocentric radial velocity of −5 km/s. It has one confirmed planet.

Phi4 Ceti is a solitary, orange-hued star in the equatorial constellation Cetus. It is faintly visible to the naked eye with an apparent visual magnitude of 5.61. Based upon an annual parallax shift of 9.76 mas as seen from Earth, it is located approximately 334 light years from the Sun. At that distance, the visual magnitude of the star is diminished by an extinction factor of 0.10 due to interstellar dust, giving it an absolute magnitude of 0.70. It is drifting closer with a radial velocity of −19 km/s.

63 Ceti is a star in the constellation of Cetus, located just over a degree south of the celestial equator. With an apparent magnitude of about 5.9, the star is barely visible to the naked eye as a dim, orange-hued point of light. Parallax estimates put it at a distance of about 390 light years away from the Earth, and it is drifting further away with a radial velocity of 28 km/s.

References

  1. 1 2 3 4 5 6 7 Vallenari, A.; et al. (Gaia Collaboration) (2022). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy & Astrophysics . arXiv: 2208.00211 . doi: 10.1051/0004-6361/202243940 . Gaia DR3 record for this source at VizieR.
  2. 1 2 3 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv: 1108.4971 . Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID   119257644.
  3. 1 2 Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
  4. ↑ 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 .
  5. 1 2 3 4 5 6 7 Gallenne, A.; et al. (August 2018). "Fundamental properties of red-clump stars from long-baseline H-band interferometry". Astronomy & Astrophysics. 616: 12. arXiv: 1806.09572 . Bibcode:2018A&A...616A..68G. doi:10.1051/0004-6361/201833341. S2CID   119331707. A68.
  6. 1 2 3 4 Teng, Huan-Yu; Sato, Bun'ei; et al. (August 2023). "Revisiting Planetary Systems in Okayama Planet Search Program: A new long-period planet, RV astrometry joint analysis, and multiplicity-metallicity trend around evolved stars". Publications of the Astronomical Society of Japan . arXiv: 2308.05343 .
  7. 1 2 3 4 5 Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics . 616. A1. arXiv: 1804.09365 . Bibcode: 2018A&A...616A...1G . doi: 10.1051/0004-6361/201833051 . Gaia DR2 record for this source at VizieR.
  8. ↑ "75 Cet". SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 2019-08-01.
  9. ↑ Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv: 0806.2878 . Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. S2CID   14878976.
  10. ↑ (in Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 7 月 11 日
  11. 1 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. S2CID   119197073.
  12. ↑ Square root of luminosity means that an Earth like planet would have to be >7 AU from the star.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.