Eggshell Planets Have a Thin Brittle Crust With No Tectonics – Unlikely To Be Habitable

With more than 700 marsquakes detected so far, scientists have a clearer picture of the interior structure of Mars than ever before. That picture shows Mars has a liquid metal core, a thick mantle with a rocky layer above a more fluid layer, and a crust that is proportionally thicker than Earth’s.

Tread Lightly: Strange “Eggshell Planets” Possible Around Other Stars

Scientists figure out what happens to Earth's disappearing crust