Stellar members of binary systems are formed from the same material, and therefore they should be chemically identical. However, recent studies have unveiled chemical differences between the two members of binary pairs composed of Sun-like stars. These chemically inhomogeneous binaries represent one of the most contradictory examples in stellar astrophysics and a source of tension between theory and observations. It is still unclear whether the abundance variations are the result of inhomogeneities in the protostellar gas clouds or are due to planet engulfment events that occurred after the stellar formation. The former scenario undermines the general belief that the chemical makeup of stars provides the fossil information of the environment in which they formed, whereas the second scenario would shed light on the possible evolutionary paths of planetary systems. Our study provides compelling evidence in favour of the planet engulfment scenario. We also establish that planet engulfment events occur in Sun-like stars with a 20–35% probability. Therefore, an important fraction of planetary systems undergo very dynamical evolutionary paths that critically modify their architectures, unlike our calm Solar System. This study opens the possibility of using chemical abundances of stars to identify which ones are the most likely to host Solar System analogues.

双星系统的恒星成员是由相同的材料形成的，因此它们在化学上应该是相同的。然而，最近的研究揭示了由类太阳恒星组成的双星对的两个成员之间的化学差异。这些化学上不均匀的双星代表了恒星天体物理学中最矛盾的例子之一，也是理论与观测之间紧张的根源。目前尚不清楚丰度变化是由于原恒星气体云中的不均匀性，还是由于恒星形成后发生的行星吞噬事件。前一种情况破坏了普遍的信念，即恒星的化学成分提供了它们形成环境的化石信息，而第二种情况将揭示行星系统可能的进化路径。我们的研究提供了有利于行星吞没情景的令人信服的证据。我们还确定行星吞噬事件发生在类太阳恒星中的概率为 20-35%。因此，与我们平静的太阳系不同，行星系统的重要部分经历了非常动态的进化路径，这些路径对其结构进行了批判性修改。这项研究开启了使用恒星的化学丰度来确定哪些恒星最有可能拥有太阳系类似物的可能性。与我们平静的太阳系不同，行星系统的重要部分经历了非常动态的进化路径，这些路径对其结构进行了批判性修改。这项研究开启了使用恒星的化学丰度来确定哪些恒星最有可能拥有太阳系类似物的可能性。与我们平静的太阳系不同，行星系统的重要部分经历了非常动态的进化路径，这些路径对其结构进行了批判性修改。这项研究开启了使用恒星的化学丰度来确定哪些恒星最有可能拥有太阳系类似物的可能性。