Kepler-20b is an
exoplanet orbiting
Kepler-20
Kepler-20 is a star 929 light-years from Earth in the constellation Lyra with a system of six known planets. The apparent magnitude of this star is 12.51, so it cannot be seen with the unaided eye. Viewing it requires a telescope with an a ...
in a system 922 light years from Earth.
It is classified as a
Super-Earth
A super-Earth is an extrasolar planet with a mass higher than Earth's, but substantially below those of the Solar System's ice giants, Uranus and Neptune, which are 14.5 and 17 times Earth's, respectively.
The term "super-Earth" refers only to ...
, as it has a radius and mass greater than that of
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 about 1.87 , it would most likely be a
Mini-Neptune
A Mini-Neptune (sometimes known as a gas dwarf or transitional planet) is a planet less massive than Neptune but resembling Neptune in that it has a thick hydrogen–helium atmosphere, probably with deep layers of ice, rock or liquid oceans (mad ...
, but its high mass of 9.7 implies that it is an iron-rich rocky world. Along with the other four planets in the system, Kepler-20b was announced on 20 December 2011.
References
Exoplanets discovered in 2011
B
Transiting exoplanets
20b
Super-Earths
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