Kepler-20f

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Kepler-20f
Extrasolar planet List of extrasolar planets
Kepler-20f Planet.jpg
An artist's depiction of Kepler-20f
Parent star
Star Kepler-20 (KOI-070)
Constellation Lyra
Right ascension (α) 19h 10m 47.524s
Declination (δ) +42° 20′ 19.30″
Apparent magnitude (mV) 12.51
Mass (m) 0.912 ± 0.035 M
Radius (r) 0.944+0.06
−0.095
 R
Temperature (T) 5,466 ± 93 K
Metallicity [Fe/H] 0.02 ± 0.04
Age 8.8+4.7
−2.7
 Gyr
Physical characteristics
Mass (m) 0.66-3.04 M
Radius (r) 1.034 +0.100
−0.127
R
Temperature (T) 705 K
Orbital elements
Semimajor axis (a) 0.1104 AU
Eccentricity (e) <0.32
Orbital period (P) 19.57706 d
Inclination (i) 88.68 +0.14
−0.17
Discovery information
Discovery date 20 December 2011
Discoverer(s) Kepler team
Discovery method Transit (Kepler Mission)
Discovery status Conference announcement

Kepler-20f is an exoplanet orbiting Kepler-20. The planet is notable as it has the closest radius to Earth known so far. The planet is fourth closest to the star, and at 705 K, too hot to have liquid water on its surface. Instead, it is expected to have an atmosphere of water vapour. Along with the other four planets in the system, Kepler-20f was announced on December 20, 2011.

Orbit[edit]

Kepler-20e and Kepler-20f compared to Venus and Earth

With a semimajor axis of 0.1104AU, Kepler-20f's orbit has a period of 19.57706 days (with an extremely small margin of error). The planet also has an inclination of 88.68°, which of course makes its transits observable from the Solar System. Like the other planets of the system, the planet has a high maximum eccentricity of 0.32.