Telltale 'twist' points to the birth of a baby alien world Scott Sutherland mardi, 26 mai 2020 à 08:45 - Astronomers spotted signs of brand new exoplanet forming around another star. Astronomers have made another stride forward in their quest to image the birth of a planet around another star directly. For decades, scientists have been developing the basic ideas about how planets form around stars. First, a star forms from a collapsing cloud of gas and dust. The remaining material surrounding the star is spun into a disk by the star's rotation, and parts of that disk clump together due to gravity. As these clumps gather more material to them, first planetesimals form, then protoplanets, and finally planets.