Beta Ceti

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**Beta Ceti**
Observation data Epoch J2000
Constellation	Cetus
Right ascension	00^h 43^m 35.2^s
Declination	-17° 59′ 12″
Apparent magnitude (V)	2.04
Spectral Characteristics
Spectral type	K0 III
U-B color index	0.87
B-V color index	1.02
Variable type	None
Astrometry
Radial velocity (R_v)	+12.8 km/s
Proper motion (μ)	RA: 232.79 mas/yr Dec.: 32.71 mas/yr
Parallax (π)	34.04 ± 0.82 mas
Distance	96 ± 2 ly (29.4 ± 0.7 pc)
Absolute magnitude (M_V)	−0.31
Physical Characteristics
Mass	3 M_☉
Radius	17 R_☉
Luminosity	145 L_☉
Temperature	? K
Metallicity	?
Rotation	3 km/s. (170 days)
Age	10⁹ years
Other designations
Deneb Kaitos, Diphda, Difda al Thani, Rana Secunda, 16 Cet, Gl 31, HR 188, BD -18°115, HD 4128, GCTP 134.00, SAO 147420, HIP 3419.

Beta Ceti (β Cet / β Ceti) is the brightest star in the constellation Cetus. Although it has the Bayer designation "beta", it is actually brighter than Alpha Ceti. It also has the traditional names Deneb Kaitos or Diphda.

Deneb Kaitos is easy to locate due to its location in an otherwise dark corner of the sky.

Deneb Kaitos has a a classification of stars based initially on photospheric temperature and its associated spectral characteristics, and subsequently refined in terms of other characteristics falling on the border between G and K, making it a yellowish-orange star somewhat cooler than the Sun. In spite of its cooler nature, Deneb Kaitos is several times brighter than the Sun, as it is more massive and has several times the Sun's radius. Deneb Kaitos appears to be an older star leaving the main sequence on its way through the red giant phase of its evolution. With an apparent magnitude of 2.04 it ranks among the brighter stars in our night sky, and an absolute magnitude of −0.31. At only 96 light years from the Earth, Deneb Kaitos is one of the nearer stars of a bright apparent magnitude. It can be located at declination −17° 59' 11.81" and right ascension of 00:43:35.23 (2000).

The traditional name Deneb Kaitos is Arabic for "tail of Cetus", also known as Diphda "frog", from the Arabic الضفدع الثاني aD-Dafda‘ aθ-θānī "the second frog").