Analyzing a sample of 300 of the best-characterized planetary systems among the more than 1,000 known in the Milky Way, an international research team led by the Italian National Institute for Astrophysics (INAF) has discovered that the multiplanet systems identified so far belong to two distinct “families.”

The study, published in Nature Astronomy, demonstrates for the first time a true “genetic link” between the host star and its planets that shapes the birth, dynamical evolution and future stability of the entire planetary system.