Rho Persei

ρ Persei

Template:Location mark Location of ρ Persei (circled)
Observation data Epoch J2000      Equinox J2000
Constellation	Perseus
Right ascension	Template:RA
Declination	Template:DEC
Apparent magnitude (V)	+3.39
Characteristics
Evolutionary stage	AGB
Spectral type	M4 II
U−B Template:Engvar	+1.79
B−V Template:Engvar	+1.65
Variable type	SRb
Astrometry
Radial velocity (Rv)	Template:Val km/s
Proper motion (μ)	RA: +129.22 mas/yr Dec.: –105.70 mas/yr
Parallax (π)	10.60±0.25 mas
Distance	Template:Rnd ± Template:Rnd ly (Template:Rnd ± Template:Rnd pc)
Absolute magnitude (MV)	−1.7
Details
Mass	Template:Val Template:Solar mass
Radius	Template:Val Template:Solar radius
Luminosity	Template:Val Template:Solar luminosity
Surface gravity (log g)	Template:Val cgs
Temperature	Template:Val K
Metallicity [Fe/H]	−0.15 dex
Rotational velocity (v sin i)	11.2 km/s
Age	440 Myr
Metallicity [Fe/H]	{{{metal_fe2}}} dex
Other designations
Template:Odlist
Database references
SIMBAD	data

Rho Persei, Latinized from ρ Persei, is a star in the northern constellation of Perseus. It has the traditional name Gorgonea Tertia Template:IPAc-en, being the third member of the quartet called the Gorgonea in reference to the Gorgons from the legend of Perseus. An apparent visual magnitude of +3.39 makes it visible to the naked eye, but a challenge to view from a well-lit urban environment. Based upon parallax measurements, it is located at a distance of roughly Template:Convert from Earth.

File:RhoPerLightCurve.png

A visual band light curve for Rho Persei, plotted from AAVSO data

Johann Schmidt discovered that Rho Persei is a variable star, in 1854. Rho Persei is a semiregular variable star, whose apparent magnitude varies between 3.3 and 4.0 with periods of 50, 120 and 250 days. The star has reached the asymptotic giant branch of its evolution. It is a bright giant star with a stellar classification of M4 II. The outer envelope has an effective temperature of 3,479 K, giving it the red-orange hue of an M-type star.

This star has a mass 1.9 times the mass of the Sun, while its radius has expanded to 143 times solar. It is radiating some 2,700 times the Sun's luminosity. Rho Persei is losing mass at the rate of Template:Val solar masses per year, or the equivalent of the Sun's mass every 83 million years. It is about 440 million years in age.

Naming

In Chinese, (), meaning Mausoleum, refers to an asterism consisting of ρ Persei, 9 Persei, τ Persei, ι Persei, κ Persei, β Persei, 16 Persei and 12 Persei. Consequently, the Chinese name for ρ Persei itself is (, Template:Langx.).

External links

• Gorgonea Tertia