14 Andromedae
Encyclopedia
14 Andromedae or 14 And is an orange giant star
Star
A star is a massive, luminous sphere of plasma held together by gravity. At the end of its lifetime, a star can also contain a proportion of degenerate matter. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth...

 approximately 258 light-year
Light-year
A light-year, also light year or lightyear is a unit of length, equal to just under 10 trillion kilometres...

s away in the constellation
Constellation
In modern astronomy, a constellation is an internationally defined area of the celestial sphere. These areas are grouped around asterisms, patterns formed by prominent stars within apparent proximity to one another on Earth's night sky....

 of Andromeda
Andromeda (constellation)
Andromeda is a constellation in the northern sky. It is named after Andromeda, the princess in the Greek legend of Perseus who was chained to a rock to be eaten by the sea monster Cetus...

. The star is a suspected variable star
Variable star
A star is classified as variable if its apparent magnitude as seen from Earth changes over time, whether the changes are due to variations in the star's actual luminosity, or to variations in the amount of the star's light that is blocked from reaching Earth...

. It is thought that 14 Andromedae was formerly a white
White main sequence star
An A-type main-sequence star is a main-sequence star of spectral type A and luminosity class V. These stars have spectra which are defined by strong hydrogen Balmer absorption lines...

 or a yellow-white dwarf
Yellow-white dwarf
An F-type main-sequence star is a main-sequence, hydrogen-fusing star of spectral type F and luminosity class V. These stars have from 1.0 to 1.4 times the mass of the Sun and surface temperatures between 6,000 and 7,600 K., Tables VII and VIII. This temperature range gives the F-type stars a...

 star early in its life. As of 2008, an extrasolar planet
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...

 is thought to be orbiting the star, being one of the few known planets to be orbiting an evolved intermediate-mass star.

Planetary system

In 2008, a planet
Extrasolar planet
An extrasolar planet, or exoplanet, is a planet outside the Solar System. A total of such planets have been identified as of . It is now known that a substantial fraction of stars have planets, including perhaps half of all Sun-like stars...

 (designated 14 Andromedae b
14 Andromedae b
14 Andromeda b or 14 And b is an extrasolar planet approximately 249 light years away in the constellation of Andromeda. The 186-day period planet orbits about 83% the Earth-Sun distance from the giant star 14 Andromedae. It has a minimum mass 4.8 times the mass of Jupiter...

) was announced to be orbiting the star. The planet was found to have a minimum mass
Minimum mass
In astronomy, minimum mass is the lower-bound calculated mass of observed objects such as planets, stars and binary systems, nebulae, and black holes. Minimum mass is a widely cited statistic for extrasolar planets...

 of 4.8 Jupiter mass
Jupiter mass
Jupiter mass , is the unit of mass equal to the total mass of the planet Jupiter . Jupiter mass is used to describe masses of the gas giants, such as the outer planets and extrasolar planets. It is also used in describing brown dwarfs....

es and orbiting in a circular orbit that takes 186 day
Day
A day is a unit of time, commonly defined as an interval equal to 24 hours. It also can mean that portion of the full day during which a location is illuminated by the light of the sun...

s to complete. The planet is one of the innermost planets around an evolved intermediate-mass star (such planets have only been discovered in clump giants).
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