Mercury's Massive Core Creates Dramatic Surface Scarring

At the edge of the solar system's inner reaches, Mercury stands as a world defined by its own extremity — a planet so dominated by its metallic heart that the thin rocky shell surrounding it could not hold itself together. As the core cooled and contracted over billions of years, the crust buckled into vast cliff formations hundreds of kilometers long, writing the story of planetary stress directly onto the surface. Mercury's unusual proportions, with a core filling 85 percent of its radius, make it an outlier among planets and a window into the violent, formative era when worlds were still be