The primary, component A, is of
magnitude 3.71 and
spectral class G8IV. It has a very low level of
surface magnetic activity and may be in a state similar to a
Maunder minimum. The activity shows a cycle of . The star displays
solar-like oscillations. Since 1943, the
spectrum of this star has served as one of the stable anchor points by which other stars are classified. This is an aging
subgiant star that has exhausted the supply of hydrogen at its core and is
evolving into a
giant. Its
angular diameter has been precisely determined using
interferometry at the
Very Large Telescope and the
CHARA array, the average of both measurements, combined with its estimated distance, result in a radius 3.096 times the
radius of the Sun. It has a mass 24% greater than
the Sun's, a luminosity 5.9 times that
of the Sun, and an
effective temperature of 5,060
K. The 12th magnitude secondary companion, designated component B, is a double-lined
spectroscopic binary, which is at an
angular separation of 13
arcseconds from the primary. It has a
stellar classification of M2.5 V, matching a
class M red dwarf. ==In culture==