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Exoplanets

An artist’s impression shows an imagined view from the surface of one of the planets orbiting the Trappist-1 starAn exoplanet, or extrasolar planet, is a planet outside our Solar System that orbits another star. The first detection of an exoplanet was confirmed in 1995. Named 51 Pegasi b, it is a giant planet, not unlike Jupiter. Since then, more than 4000 exoplanets, belonging to more than 3000 different solar systems, have been discovered. In August 2016, an Earth-sized world was detected orbiting Proxima Centauri, the nearest star to the Sun. A number of stars have exoplanets orbiting in what is known as the “habitable zone”, a region lying at a certain distance from the star within which a planet’s surface temperature will allow liquid water—and therefore potentially life—to exist. Scientists estimate that there are as many as 40 billion potentially habitable Earth-sized planets in the Milky Way Galaxy. With so many of these worlds, the chances of life existing elsewhere in the Galaxy seem high.


An artist's impression of Kepler-62f, an exoplanet orbiting within the habitable zone of the star Kepler-62, discovered by NASA's...Read More >>An artist's impression of Kepler-62f, an exoplanet orbiting within the habitable zone of the star Kepler-62, discovered by NASA's Kepler spacecraft in 2012. It is located about 1200 light years from Earth in the constellation of Lyra. The exoplanet was found by using the transit method.
High Accuracy Radial velocity Planet Searcher (HARPS), installed on the 3.6-metre telescope at the European Southern Observatory...Read More >>High Accuracy Radial velocity Planet Searcher (HARPS), installed on the 3.6-metre telescope at the European Southern Observatory (ESO), La Silla, Chile

Detecting exoplanets

More than 2300 exoplanets have been discovered by the Kepler Space Telescope, while the High Accuracy Radial velocity Planet Searcher (HARPS), installed on the 3.6-metre telescope at the European Southern Observatory (ESO), La Silla, Chile, has discovered about a hundred.

The first confirmation of an exoplanet orbiting a main-sequence star was made in 1995, when a giant planet was found in a four-day orbit around the nearby star 51 Pegasi.

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