Delta Ceti

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Delta Ceti
Observation data
Epoch J2000.0      Equinox J2000.0
Constellation Cetus
Right ascension 02h 39m 28.956s[1]
Declination +00° 19′ 42.63″[1]
Apparent magnitude (V) +4.08
Characteristics
Spectral type B2 IV[2]
Variable type β Cep[2]
Astrometry
Proper motion (μ) RA: 12.85 ± 0.17[1] mas/yr
Dec.: –2.94 ± 0.11[1] mas/yr
Parallax (π) 5.02 ± 0.15[1] mas
Distance 650 ± 20 ly
(199 ± 6 pc)
Details
Mass 8.4 ± 0.7[2] M
Radius 4.6 ± 0.8[2] R
Luminosity 4,000[2] L
Surface gravity (log g) 4.05 ± 0.20[2] cgs
Temperature 21,900 ± 1,000[2] K
Rotational velocity (v sin i) 7 ± 4[2] km/s
Other designations
82 Ceti, HD 16582, HR 779, SAO 110665, FK5 91, BD-00 406, HIP 12387.

Delta Ceti (δ Ceti, δ Cet) is a Class B2, fourth-magnitude star in the constellation Cetus.

Properties[edit]

Delta Ceti is positioned very near the celestial equator and is located about 0.74 degrees WNW of the spiral galaxy M77. Delta Ceti is a blue giant star located about 660 light-years from Earth.

It is a Beta Cephei variable.[2]

Name[edit]

This star, along with α Cet (Menkar), λ Cet (Menkar), γ Cet (Kaffaljidhma), μ Cet, ξ1 Cet and ξ2 Cet were Al Kaff al Jidhmah, "the Part of a Hand".[3]

According to the catalogue of stars in the Technical Memorandum 33-507 - A Reduced Star Catalog Containing 537 Named Stars, Al Kaff al Jidhmah were the title for five stars :γ Cet as Kaffaljidhma, ξ1 Cet as Al Kaff al Jidhmah I, ξ2 Cet as Al Kaff al Jidhmah II, δ Cet as Al Kaff al Jidhmah III and μ Cet as Al Kaff al Jidhmah IV (exclude α Cet and λ Cet)[4]

In Chinese, 天囷 (Tiān Qūn), meaning Circular Celestial Granary, refers to an asterism consisting of δ Ceti, α Ceti, κ1 Ceti, λ Ceti, μ Ceti, ξ1 Ceti, ξ2 Ceti, ν Ceti, γ Ceti, 75 Ceti, 70 Ceti, 63 Ceti and 66 Ceti. Consequently, δ Ceti itself is known as 天囷九 (Tiān Qūn jiǔ, English: the Ninth Star of Circular Celestial Granary.)[5]

References[edit]

External links[edit]

"HD 16582 -- Variable Star". SIMBAD Astronomical Database. Retrieved 2006-11-05.