Extrasolar planet

2 January 2013: Astronomers state that the Milky Way may contain as many as 400 billion exoplanets, with almost every star hosting at least one planet.[1][2][3] An exoplanet or extrasolar planet is a planet outside the Solar System. Around 1800 such planets have been discovered[5][6][7] (1783 planets in 1105 planetary systems including 460 multiple planetary systems as of 18 April 2014).[8] The nearest known exoplanet, if confirmed, would be Alpha Centauri Bb, but there is some doubt about its existence. For centuries philosophers and scientists supposed that extrasolar planets existed, but there was no way of detecting them or of knowing their frequency or how similar they might be to the planets of the Solar System. The discovery of extrasolar planets has intensified interest in the search for extraterrestrial life, particularly for those that orbit in the host star's habitable zone where it is possible for liquid water (and therefore life) to exist on the surface. Direct imaging[edit]

Exoplanet Orbit Database | Exoplanet Data Explorer