Mercury Is Still Shrinking After Billions of Years: How Its Giant Cooling Core Is Cracking the Planet’s Thin Crust

Mercury is still shrinking after billions of years: How its giant cooling core is cracking the planet’s thin crust

Mercury's massive metallic core leads to a contraction of its rocky exterior, resulting in numerous fractures and cliffs spanning hundreds of kilometers. Recent studies have uncovered fault scarps that suggest active tectonic processes are still at play on the planet. Researchers examine these formations to gain insight into Mercury's internal mechanics, with future missions expected to deliver clearer images of these relatively young tectonic a…

Mercury is the Solar System’s smallest planet, but its metallic core fills about 85 per cent of its radius, leaving a rocky shell so thin that cooling has crumpled the surface into cliffs hundreds of kilometres long

Mercury is the smallest planet in the Solar System, but most of the distance from its centre to its surface passes through metal. NASA puts the radius of Mercury’s metallic core at about 2,074 kilometres, compared with a planetary radius of 2,440 kilometres. That is roughly 85 per cent of the planet’s radius. The percentage needs reading carefully. It describes radius, not volume, and it does not mean the remaining 15 per cent is all crust. NASA…