For nearly ten years, astronomers have been trying to demonstrate the existence of a massive object thought to be orbiting in the outer reaches of the Solar System. Although the hypothesis is widely...
Alessandro Morbidelli is a specialist in the evolution and formation of planetary systems, and holds the planetary formation Chair at the Collège de France. The astrophysicist looks back on his...
Less than a month after US astronomers postulated the existence of a ninth planet in the Solar System, a French team managed to halve the possible search area. One of the researchers responsible for...