Kepler-452b
Kepler-452b (sometimes quoted to be an Earth 2.0 or Earth's Cousin based on its characteristics; also known by its Kepler Object of Interest designation KOI-7016.01) is a super-Earth exoplanet orbiting within the inner edge of the habitable zone of the sun-like star Kepler-452 and is the only planet in the system discovered by Kepler. It is located about 1,400 light-years (430 pc) from Earth in the constellation of Cygnus.
Artist's impression of Kepler-452b (center), depicted here as a rocky planet in the habitable zone with extensive cloud cover. The actual appearance and composition of the exoplanet is unknown. | |
Discovery | |
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Discovered by | Kepler Science team |
Discovery site | Kepler |
Discovery date | 23 July 2015 (announced) |
Detection method | Transit |
Designations | |
Alternative names | KOI-7016.01 |
Orbital characteristics | |
Semi-major axis | 1.046+0.019 −0.015 AU |
Orbital period (sidereal) | 384.843+0.007 −0.012 d |
Inclination | 89.806+0.134 −0.049 |
Star | Kepler-452 |
Physical characteristics | |
Mean radius | 1.5+0.32 −0.22 R🜨 |
Mass | 5 ± 2 ME |
Surface gravity | 1.9+1.5 −1.0 (est.) g |
Temperature | Teq: 265K+15 −13 (265 K (−8 °C; 17 °F)) |
Kepler-452b orbits its star at a distance of 1.04 AU (156 million km; 97 million mi) from its host star (nearly the same distance as Earth from the Sun), with an orbital period of roughly 385 days, has a mass at least five times that of Earth, and has a radius of around 1.5 times that of Earth. It is the first potentially rocky super-Earth planet discovered orbiting within the habitable zone of a very sun-like star. However, it is unknown if it is entirely habitable, as it is receiving slightly more energy from its star than Earth and could be subjected to a runaway greenhouse effect.
The Kepler space telescope identified the exoplanet, and its discovery was announced by NASA on 23 July 2015. The planet is about 1,800 light-years (550 pc) away from the Solar System. At the speed of the New Horizons spacecraft, at about 59,000 km/h (16,000 m/s; 37,000 mph), it would take approximately 30 million years to get there.