La révolution des exoplanètes

International audienceMore than 3600 planets are known today outside the Solar System. We describe the different ways to find them, and the astonishing variety in their masses, in their orbits, and in their physical properties. The ways they are formed are discussed, with the Solar System as an example. The most exciting prospect open to the discovery of extrasolar planets is the search for planets located neither too close nor too far from their star, where life could develop. Our anthropocentrism suggests that they must have a mass close to that of the Earth, but in reality nothing prevents massive planets - super-Earths - or, on the contrary, less massive planets, to carry life. To characterize them and to look for clues of a form of life is one of the main challenges of the coming years