NASA scientists find ancient impact fragments deep inside Mars

NASA-supported scientists analyzing data from the InSight probe have identified “ancient fragments” deep inside Mars, CE Report quotes Kosova Press.

Seismic readings reveal that the planet’s mantle is filled with kilometer-scale chunks interpreted as debris from colossal impacts during Mars’ violent early history, preserved for billions of years. This is the clearest evidence yet that the Red Planet’s interior still contains physical remnants of its early collisions.

Mars’ mantle contains scattered blocks, including fragments up to about 4 kilometers wide, arranged in clusters surrounded by smaller pieces. Researchers conclude these are relics of ancient impact material and early crust that sank and became trapped as Mars solidified.

InSight’s seismometer measured how marsquakes’ waves slowed, sped up, and scattered traveling through the interior. Modeling these distortions produced a “bloated” mantle map consistent with strong, trapped inclusions embedded in softer rock.

Since Mars lacks plate tectonics, these inclusions have remained in place for billions of years, making them detectable today.

The size, distribution, and seismic signatures match expectations for material left by early giant impacts that generated global magma oceans on young rocky planets. On Mars, these remnants appear frozen in place rather than recycled like on Earth.

NASA describes the mantle as “filled with ancient fragments,” highlighting their age and impact origin.

These fragments preserve a physical record of Mars’ earliest impacts and provide constraints on the planet’s formation and cooling. The discovery also improves estimates of mantle viscosity and mixing rates—key parameters for thermal evolution models.

Researchers plan to reanalyze InSight’s full catalog to refine a 3D mantle map, compare fragment distributions with major known impact basins, and test whether different regions contain varying fragment sizes.