Gorgonea Tertia Rho Persei

Stellar classification



  • X -147
  • Y -88
  • Z -256
→ Sol: 308

Object type

  • Semi-regular pulsating Star
  • Star
  • Infra-Red source
  • High proper-motion Star
  • UV-emission source
  • Variable Star
simbad:* rho Per


Rho Persei (Rho Per, ρ Persei, ρ Per) is a star in the northern constellation of Perseus. It has the traditional name Gorgonea Tertia, 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 308 light-years (94 pc) from Earth.

Rho Persei is a semiregular variable star of the μ Cephei type, 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 near the tip of the red giant branch with a stellar classification of M4 II. The outer envelope has an effective temperature of 4,111 K, giving it the red-orange hue of an M-type star.

This star has a mass five times the mass of the Sun, while its radius has expanded to 150 times solar. It is radiating some 2,290 times the Sun's luminosity. Rho Persei is losing mass at the rate of 1.2 × 10−8 solar masses per year, or the equivalent of the Sun's mass every 83 million years. It is about 440 million years in age.

This article uses material from the Wikipedia article "Rho Persei", which is released under the Creative Commons Attribution-Share-Alike License 3.0.