Kepler-20e

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Kepler-20e
Extrasolar planet List of extrasolar planets
Kepler-20e Planet.jpg
An artist's depiction of Kepler-20e
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) 0.39-1.67 M
Radius (r) 0.868 +0.074
−0.096
R
Temperature (T) 1040 K
Orbital elements
Semimajor axis (a) 0.0507 AU
Eccentricity (e) <0.28
Orbital period (P) 6.098493 d
Inclination (i) 87.50 +0.33
−0.34
Discovery information
Discovery date 20 December 2011
Discoverer(s) Kepler team
Discovery method Transit (Kepler Mission)
Discovery status Conference announcement

Kepler-20e is an exoplanet orbiting Kepler-20. The planet is notable as it is the first planet with a smaller radius than Earth found orbiting a Sun-like star. The planet is second closest to the star after Kepler-20b, and at 1040 K, it is far too hot to have liquid water on its surface. Along with the other four planets in the system, Kepler-20e was announced on December 20, 2011.

Orbit[edit]

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

With a semimajor axis of 0.0507 AUs, Kepler-20e's orbit has a period of 6.098 days (with an extremely small margin of error). The orbit has an inclination of 87.50°, making its transits observable from the Solar System. Like the other planets of the system, the planet has a high maximum eccentricity of 0.28, but the lowest in that system.