κ Delphini (Latinised as Kappa Delphini, abbreviated to κ Del or kappa Del) is a

binary star system A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in wh ...

in the

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 ...

Delphinus Delphinus (Pronounced or ) is a small constellation in the Northern Celestial Hemisphere, close to the celestial equator. Its name is the Latin Latin (, or , ) is a classical language belonging to the Italic branch of the Indo-Europea ...

. It is faintly visible to the naked eye, with an

apparent 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 li ...

of 5.05. It is located about 98.8

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, based on its

parallax Parallax is a displacement or difference in the apparent position of an object viewed along two different lines of sight and is measured by the angle or semi-angle of inclination between those two lines. Due to foreshortening, nearby objects ...

. Kappa Delphini is an

astrometric binary A binary star is a system of two stars that are gravitationally bound to and in orbit around each other. Binary stars in the night sky that are seen as a single object to the naked eye are often resolved using a telescope as separate stars, in wh ...

. The primary star is an early G-type

subgiant 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 of ...

star. It has a mass 1.61 times that of the Sun, and is 6.8 times more luminous. The companion star regularly perturbs the G-type primary star primary, causing it to wobble around the

barycenter In astronomy, the barycenter (or barycentre; ) is the center of mass of two or more bodies that orbit one another and is the point about which the bodies orbit. A barycenter is a dynamical point, not a physical object. It is an important conc ...

. From this, an orbital period of 45 years has been calculated. The secondary star is a low-mass star, at only . A third star is 12th magnitude ADS 14101 B, away in 2001, but it is a background object. HD 196794 is an 8th magnitude K2

away is at the same distance as κ Delphini and shares a common proper motion.

References

{{DEFAULTSORT:Kappa Delphini Delphini, Kappa Delphinus G-type subgiants K-type subgiants 196755 7896 101916 Delphini, 07 Durchmusterung objects Astrometric binaries