star
A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...
located around 750
light year
A light-year, alternatively spelled light year, is a large unit of length used to express astronomical distances and is equivalent to about 9.46 trillion kilometers (), or 5.88 trillion miles ().One trillion here is taken to be 1012 ...
s away from the Sun in the northern
constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object.
The origins of the e ...
of Hercules. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.67 The brightness of the star is diminished by an extinction of 0.21 due to interstellar dust. It is moving closer to the Earth with a heliocentric
radial velocity
The radial velocity or line-of-sight velocity, also known as radial speed or range rate, of a target with respect to an observer is the temporal rate of change, rate of change of the distance or Slant range, range between the two points. It is e ...
of −24.5 km/s. This star, together with 95 Her, 102 Her, and 109 Her, made up the obsolete constellation Cerberus.
This object has a
stellar classification
In astronomy, stellar classification is the classification of stars based on their stellar spectrum, spectral characteristics. Electromagnetic radiation from the star is analyzed by splitting it with a Prism (optics), prism or diffraction grati ...
of K0.5IIb, which indicates it is an evolvedbright giant. With the supply of hydrogen at its core exhausted, the star has expanded to 51 times the Sun's radius. It is radiating around 919 times the luminosity of the Sun from its enlarged
photosphere
The photosphere is a star's outer shell from which light is radiated.
The term itself is derived from Ancient Greek roots, φῶς, φωτός/''phos, photos'' meaning "light" and σφαῖρα/''sphaira'' meaning "sphere", in reference to it ...
at an
effective temperature
The effective temperature of a body such as a star or planet is the temperature of a black body that would emit the same total amount of electromagnetic radiation. Effective temperature is often used as an estimate of a body's surface temperature ...
of 4,471 K. It is generally deficient in metal elements, but appears weakly enhanced in barium and other heavier elements. This is a suspected barium star and hence may have a white dwarf companion in orbit.