The traditional theory, known as the "canonical model," holds that the Earth and other rocky planets in our solar system formed through a process of accretion, in which small, rocky bodies called planetesimals gradually collided and stuck together to form larger and larger objects, eventually leading to the formation of planets.
However, new experiments conducted by a team of researchers from the University of Chicago and the Carnegie Institution for Science suggest that the canonical model may not be able to fully explain the formation of rocky planets. The experiments showed that collisions between planetesimals at high velocities can actually cause them to shatter and disperse rather than stick together.
The researchers conducted the experiments using a high-speed impact facility at the University of Chicago. They fired projectiles made of various materials, including ice and rock, at different speeds at targets made of the same materials. The experiments showed that collisions at high velocities, such as those that would occur during the early stages of planet formation, can cause the planetesimals to shatter and disperse, rather than stick together.
This suggests that the canonical model, which assumes that planetesimals always stick together upon impact, may not be accurate. Instead, the researchers propose a new model that takes into account the possibility of shattering and dispersal of planetesimals during high-velocity collisions.
The new model suggests that the early stages of planet formation may have been more complex and chaotic than previously thought, and that the process of accretion may have been accompanied by significant amounts of fragmentation and dispersal of material. This could have implications for our understanding of the composition and structure of rocky planets, as well as the formation of the Earth and other planets in our solar system.
Further experiments and research will be needed to better understand the process of planet formation and to refine the models used to describe it.
