Kepler-11 e

Kepler-11e is an exoplanet (extrasolar planet) discovered in the orbit of the sunlike star Kepler-11. It is the fourth of six planets around Kepler-11 discovered by NASA's Kepler space telescope. Kepler-11e was found by using the transit method, in which the dimming effect that a planet causes as it crosses in front of its star is measured. Kepler-11e is most likely a gas giant like Neptune, having a density that is less than that of Saturn, the least dense planet in the Solar System. Its low density can probably be attributed to a large hydrogen and helium atmosphere. Kepler-11e has a mass eight times of Earth's mass and a radius 4.5 times that of Earth. The planet orbits its star every 31 days in an ellipse that would fit within the orbit of Mercury. Kepler-11e was announced on February 2, 2011 with its five sister planets after it was confirmed by several observatories.

==Name and discovery== At the time when Kepler-11 was first noted as a host to a potential transit event, the star was given the designation KOI-157. It was later assigned the name "Kepler-11" after the Kepler spacecraft, a NASA satellite tasked with discovering planets in transit of, or crossing in front of, their stars. This transit causes a slight and regular change in the host star's brightness, which can then tested to prove the planet's existence and, later, to extrapolate the orbital parameters of the planet. Kepler-11e is first given the designation by its host star, Kepler-11. Since Kepler-11e was announced with five other planets, the letters added to the star are sorted by the planet's distance from its star. Kepler-11e is the fourth planet from Kepler-11, it is given the designation "e".