Phi Serpentis (φ Ser, φ Serpentis) is a solitary
[ star in the Serpens Caput portion of the equatorial constellation ]Serpens
Serpens ( grc, , , the Serpent) is a constellation in the northern celestial hemisphere. One of the 48 constellations listed by the 2nd-century astronomer Ptolemy, it remains one of the 88 modern constellations designated by the International ...
. Based upon an annual parallax shift of 13.52 mas as seen from Earth, it is located about 241 light years distant. The star is faintly visible to the naked eye with an apparent visual magnitude
Apparent magnitude () is a measure of the brightness of a star or other astronomical object observed from Earth. An object's apparent magnitude depends on its intrinsic luminosity, its distance from Earth, and any extinction of the object's lig ...
of +5.55.[
At the estimated age of 3.42 billion years,][ this is an ]evolved
Evolution is change in the heritable characteristics of biological populations over successive generations. These characteristics are the expressions of genes, which are passed on from parent to offspring during reproduction. Variation ...
K-type subgiant star
A subgiant is a star that is brighter than a normal main-sequence star of the same spectral class, but not as bright as giant stars. The term subgiant is applied both to a particular spectral luminosity class and to a stage in the evolution o ...
with a stellar classification of K1 IV.[ It has about 1.19][ times the mass of the Sun and around 4.2][ times the Sun's radius. The star radiates 41.7][ times the ]solar luminosity
The solar luminosity (), is a unit of radiant flux ( power emitted in the form of photons) conventionally used by astronomers to measure the luminosity of stars, galaxies and other celestial objects in terms of the output of the Sun.
One nominal ...
from its photosphere at an effective temperature of 4,493 K.[
]
References
{{DEFAULTSORT:Phi Serpentis
K-type subgiants
Serpentis, Phi
Serpens
Durchmusterung objects
142980
78132
5940