HD 77338 explained

HD 77338 is a star with a close orbiting exoplanet companion in the southern constellation of Pyxis. It is too dim to be visible with the naked eye, having an apparent visual magnitude of 8.63. The system is located at a distance of 149 light years, and it is drifting further away with a heliocentric radial velocity of 8.2 km/s.

The spectrum of this star presents as a K-type subgiant with a stellar classification of K0 IV. This indicates the star has exhausted the supply of hydrogen at its core and has begun to evolve away from the main sequence. It has 94% of the mass of the Sun and 97% of the Sun's girth. The star is spinning with a rotation period of roughly 33 days. It is radiating 71% of the luminosity of the Sun from its photosphere at an effective temperature of 5,315 K.

HD 77338 is enriched in its concentration of elements more massive than helium compared to the Sun, with a metallicity of 0.16, but is much older at an age of 9.5 billion years. It is unusually enriched in heavy elements for a star of its age. The anomalously high abundance of ions of manganese may indicate the star has recently passed through the common shell stage (engulfed a planet).

Planetary system

In 2012, a planet, named HD 77338b, was discovered by the radial velocity method on a tight orbit with uncertain eccentricity. Its equilibrium temperature is 954.8 K.[1]

Notes and References

  1. http://www.exoplanetkyoto.org/exohtml/HD_77338_b.html HD 77338 b is an exoplanet orbiting the star HD 77338, located about 149.3 light-years (45.8 pc) away from Solar System. Its discovery was publicly announced on 2012