Kepler-296e (also known by itsKepler Object of Interest designation KOI-1422.05) is a confirmed super-Earthexoplanet orbiting within thehabitable zone ofKepler-296. The planet was discovered byNASA'sKepler spacecraft using thetransit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. NASA announced the discovery of the exoplanet on 26 February 2014.^[1]

Kepler-296e was assumed to be asuper-Earth with a radius 1.75 times that ofEarth. A more revised estimate puts the planet at 1.53 Earth-radii. The planet orbits Kepler-296 once every 34.1 days at a semimajor axis distance of 0.169 AU.^[4] It would have a mass of 4.52 Earth masses, with the higher-than-Earth density suggested by exoplanetkyoto.^[5] With an Earth-like density, the mass would be 3.58 Earth masses. The planet's equilibrium temperature is 267 K (–6 °C; 21 °F), much higher than that of Earth.

The planet was announced as being located within thehabitable zone of Kepler-296. In this region,liquid water could exist on the surface of theplanet.^[6] It is likely rocky, with its relatively low radius, in contrast tof, which is larger.^[4][6] As of 2017, with an ESI of 0.85, it is the fifth-most Earth-like planet afterKepler-438b,TRAPPIST-1 d, and two Gliese-designated planets,GJ 3323 b andGliese 273 b (Luyten b) which were both discovered in 2017.^[7] The planet receives 1.4 times the Earth's solar flux, putting it well within the habitable zone and just barely beyond therunaway G line.^[7][8] According to Kopparapu et. al (2013), the planet is within the most conservative boundaries of the habitable zone.^[9] However, it has an eccentric orbit,^[4][10] with a maximum eccentricity of 0.33 to a confidence of3-sigma.^[4] The planet's equilibrium temperature varies depending on its albedo: for a non-tidally locked planet with an Earth-like albedo of 0.3, it is 234 K (–39 °C; –38 °F), and for a Venus-like albedo of 0.7, it is 189 K (–84 °C; -119 °F). For a tidally locked planet with an Earth-like albedo of 0.3, the equilibrium temperature is 278 K (5 °C; 41 °F).^[5]

According to,^[11] an Earth-size planet with eccentricity <0.1, no moons, and no obliquity orbiting at the Earth boundary within the habitable zone is tidally locked around a star with a mass of <0.42 solar masses (~M2 or later). When theSolar System is used as a yardstick, then the limit is 0.72 solar masses (~K3-4 or later). However, the orbit of planet e, is likely more eccentric than the modeled fictional planet, so the planet may not have had enough time to tidally lock.^[4][10]

• Kepler-62e andf

• Habitability of red dwarf systems
• List of potentially habitable exoplanets

• NASA – Kepler Mission.
• NASA – Kepler Discoveries – Summary Table.
• NASA – Kepler-296e atThe NASA Exoplanet Archive.
• NASA – Kepler-296e atThe Exoplanet Data Explorer.
• NASA – Kepler-296e atThe Extrasolar Planets Encyclopaedia.
• Habitable Exolanets Catalog atUPR-Arecibo.

• Exoplanets discovered in 2014
• Exoplanets discovered by the Kepler space telescope
• Exoplanets in the habitable zone
• Super-Earths in the habitable zone
• Transiting exoplanets
• Kepler-296

• Articles with short description
• Short description is different from Wikidata
• Use dmy dates from January 2015