Kepler-56 is a

red giant A red giant is a luminous giant star of low or intermediate mass (roughly 0.3–8 solar masses ()) in a late phase of stellar evolution. The stellar atmosphere, outer atmosphere is inflated and tenuous, making the radius large and the surface t ...

in constellation Cygnus roughly away with slightly more mass than the

Sun The Sun is the star at the centre of the Solar System. It is a massive, nearly perfect sphere of hot plasma, heated to incandescence by nuclear fusion reactions in its core, radiating the energy from its surface mainly as visible light a ...

Characteristics

Kepler-56 is a red giant star. This means it is no longer fusing hydrogen in its core and is off the main sequence. Its mass is around 1.3 ''M''_⊙. Its radius is about 4.2 ''R''_⊙, putting the star's density at about 0.025 g/cm³. For reference, the Sun's density is about 1.408g/cm³. Its metallicity is about 0.0251 ''Z''₀/''X''₀. Its luminosity is about 9.6 ''L''_⊙, and its effective temperature is . Kepler-56 is about 3.9 billion years old, placing it as about 600 million years younger than the Sun. Its apparent magnitude is +13, making it too dim to be visible to the naked eye.

Planetary system

In 2012, scientists discovered a two-planet planetary system around Kepler-56 via the transit method. Asteroseismological studies revealed that the orbits of

Kepler-56b Kepler-56b (KOI-1241.02) is a hot Neptune—a class of exoplanets—located roughly away. It is somewhat larger than Neptune and orbits its parent star Kepler-56 and was discovered in 2013 by the Kepler Space Telescope. Planetary orbit Kepler-5 ...

and Kepler-56c are coplanar but about 45° misaligned to the host star's equator. In addition, follow-up radial velocity measurements showed evidence of a gravitational perturbator. It was confirmed in 2016 the perturbations are caused by third, non-transiting planet: Kepler-56d. The planetary system is very compact but is dynamically stable. Kepler-56 is expanding. As a result, it will devour Kepler-56b and Kepler-56c in 130 and 155 million years, respectively. 56d will be far enough to survive its parent star's red giant phase.

References

External links

Kepler-56, The Open Exoplanet Catalogue

Kepler 56, Exoplanet.eu
{{2012 in space Cygnus (constellation)

1241 Year 1241 ( MCCXLI) was a common year starting on Tuesday of the Julian calendar. Events * March 18 – Battle of Chmielnik ( Mongol invasion of Poland): The Mongols overwhelm the feudal Polish armies of Sandomierz and Kraków provinces ...

Planetary transit variables K-type giants Planetary systems with three confirmed planets