Delta Pavonis


Delta Pavonis is a star in the southern circumpolar constellation of Pavo. It has an apparent visual magnitude of 3.56, making it a fourth-magnitude star that is visible to the naked eye from the southern hemisphere. Parallax measurements from the Hipparcos satellite yield an estimated distance of from Earth. This makes it one of the nearest bright stars to the Solar System.

Observations

It is a subgiant of spectral type G8 IV; it will stop fusing hydrogen relatively soon, starting the process of becoming a red giant. Hence, Delta Pavonis is 22% brighter than the Sun, but the effective temperature of its outer atmosphere is less: 5,604 K. Its mass is 99.1% of Sol's mass, with a mean radius 122% of Sol's radius. Delta Pavonis's surface convection zone extends downward to about 43.1% of the star's radius, but only contains 4.8% of the star's mass.
Spectroscopic examination of Delta Pavonis shows that it has a higher abundance of elements heavier than helium than does the Sun. This value is typically given in terms of the ratio of iron to hydrogen in a star's atmosphere, relative to that in Sol's atmosphere. The metallicity of Delta Pavonis is approximately
This notation gives the logarithm of the iron-to-hydrogen ratio, relative to that of the Sun, meaning that Delta Pavonis's iron abundance is 214% of that of Sol. Studies have shown a correlation between abundant heavy elements in stars, and the presence of a planetary system, so Delta Pavonis has a greater than average probability of harboring planets.
The age of Delta Pavonis is approximately 6.6 to 6.9 billion years. It appears to be rotating slowly, with a projected rotational velocity of 1.0 kilometers per second.

SETI

Delta Pavonis has been identified by Maggie Turnbull and Jill Tarter of the SETI Institute as the "Best SETI target" among the 100 closest G-type stars. Properties in its favor include a high metallicity, minimal level of magnetic activity, low rotation rate, and kinematic membership in the thin disk population of the Milky Way. Gas giants orbiting in, near, or through a star's habitable zone may destabilize the orbits of terrestrial planets in that zone; the lack of detected radial velocity variation suggests that there are no such gas giants orbiting Delta Pavonis. However, observation has detected no artificial radio sources. Delta Pavonis, a close photometric match to the Sun, is the nearest solar analog that is not a member of a binary or multiple star system.

In fiction