Tau Cassiopeiae

τ Cassiopeiae

Observation data Epoch J2000.0      Equinox J2000.0
Constellation	Cassiopeia
Right ascension	23h 47m 03.455s
Declination	+58° 39′ 07.16″
Apparent magnitude (V)	+4.88
Characteristics
Spectral type	K1IIIa
U−B color index	+1.05
B−V color index	+1.11
Variable type	none
Astrometry
Radial velocity (Rv)	−21 km/s
Proper motion (μ)	RA: 60.81 ± 0.19 mas/yr Dec.: 56.47 ± 0.17 mas/yr
Parallax (π)	18.75 ± 0.20 mas
Distance	174 ± 2 ly (53.3 ± 0.6 pc)
Absolute magnitude (MV)	+1.26
Other designations
5 Cassiopeiae, HR 9008, HD 223165, BD+57°2804, FK5 3909, HIP 117301, SAO 35763

Map of the Bayer-designated stars in Cassiopeia. Tau Cassiopeiae is circled.

Tau Cassiopeiae (τ Cas, τ Cassiopeiae) is a star in the constellation Cassiopeia. τ Cassiopeiae is an orange K-type giant with an apparent magnitude of +4.88. It is approximately 174 light years from Earth.

Naming

In Chinese, 螣蛇 (Téng Shé), meaning Flying Serpent, refers to an asterism consisting of τ Cassiopeiae, α Lacertae, 4 Lacertae, π² Cygni, π¹ Cygni, HD 206267, ε Cephei, β Lacertae, σ Cassiopeiae, ρ Cassiopeiae, AR Cassiopeiae, 9 Lacertae, 3 Andromedae, 7 Andromedae, 8 Andromedae, λ Andromedae, κ Andromedae, ι Andromedae, and ψ Andromedae. Consequently, τ Cassiopeiae itself is known as 螣蛇十三 (Téng Shé shísān, English: the Thirteenth Star of Flying Serpent)

According to "Official Star Registry" from January 5th 2016 the star has been named Robert Neumüller.