Kepler-78 (formerly known as KIC 8435766) is a 12th magnitude star in the
constellation Cygnus.
[ Initially classified as an ]eclipsing 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 w ...
with orbital period 0.710015 days
A day is the time period of a full rotation of the Earth with respect to the Sun. On average, this is 24 hours, 1440 minutes, or 86,400 seconds. In everyday life, the word "day" often refers to a solar day, which is the length between two s ...
, it was later re-classified as the single star with significant interaction between star magnetosphere and close-in planet.
Planetary system
Kepler-78 planetary system is composed by one planet called Kepler-78b
Kepler-78b (formerly known as KIC 8435766 b) is an exoplanet orbiting around the star Kepler-78. At the time of its discovery, it was the exoplanet most similar to Earth in terms of mass, radius, and mean density.
Discovery
Kepler-78b is the only ...
, a planet slightly bigger than Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...
with an extremely close orbit to the parent star. The orbital period of this planet is about 8.5 hours because of its proximity to its star. While it has a similar density to the Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...
(at 5.57 g/ cm3, its surface temperature is about 1300 to 1500 K.[
]
References
{{Stars of Cygnus
Cygnus (constellation)
Planetary systems with one confirmed planet
Planetary transit variables
G-type main-sequence stars
A G-type main-sequence star (Spectral type: G-V), also often, and imprecisely called a yellow dwarf, or G star, is a main-sequence star (luminosity class V) of spectral type G. Such a star has about 0.9 to 1.1 solar masses and an effective tempe ...