Kepler-56

Kepler-56 is a red giant in constellation Cygnus roughly 3,030 ly away with slightly more mass than the Sun.

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 0.025g/cm3. For reference, the Sun's density is about 1.408g/cm3. Its metallicity is about 0.0251 Z0/X0. Its luminosity is about 9.6 L⊙, and its effective temperature is 4973 K, classifying Kepler-56 as spectral class K3III.

Kepler-56 is about 3.9 billion years old, placing it as about 600 million years younger than our 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 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.