New research suggests the interior of Mars is far messier than scientists once believed. Instead of neat, layered structures, perhaps resembling a smooth slice of Millionaire's Shortbread, Mars' mantle is more like a rocky road brownie — chunky, uneven, and filled with ancient debris from its violent beginnings.
The discovery comes from seismic data collected by NASA's InSight lander, which operated on Mars from 2018 and 2022. Researchers from Imperial College London analyzed waves from eight particularly clear marsquakes, noting interference patterns consistent with a mantle riddled with large fragments of different materials. Those fragments are estimated to be up to 2.5 miles (4 kilometers) wide.
