Rho Cassiopeiae

Stellar classification



  • X -10467
  • Y -879
  • Z -5036
→ Sol: 11,649

Object type

  • Semi-regular pulsating Star
  • Star
  • Emission-line Star
  • Infra-Red source
  • Variable Star
simbad:* rho Cas


Rho Cassiopeiae (; ρ Cas, ρ Cassiopeiae) is a yellow hypergiant star in the constellation Cassiopeia. It is about 8,200 light-years (2,500 pc) from Earth, yet can still be seen by the naked eye as it is 500,000 times brighter than the Sun. On average it has an absolute magnitude of −9.5, making it visually one of the most luminous stars known. Its diameter measures between 400 and 500 times that of the Sun, approximately 627,000,000 kilometers, or about twice the size of the Earth's orbit.

Rho Cassiopeiae is a single star, and is categorized as a semiregular variable. As a yellow hypergiant, it is one of the rarest types of stars. Only around a dozen are known in the Milky Way, but it is not the only one in its constellation which also contains V509 Cassiopeiae.

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