NASA data reveals 'lumpy' mantle inside Mars

Rocky material from ancient impacts lies scattered in giant lumps throughout Mars' mantle, offering new insights into the planet's interior and its early history, according to a new study published on Thursday.

Fragments from the aftermath of massive impacts on Mars that occurred 4.5 billion years ago have been detected deep below the planet's surface by NASA's InSight lander, which recorded the findings before its mission ended in 2022.

The ancient impacts released enough energy to melt continent-size swaths of the early crust and mantle into vast magma oceans, simultaneously injecting the impactor fragments and Martian debris deep into the planet's interior, according to the research, published in the journal Science.

The remains of these impacts still exist as lumps up to four km across and scattered throughout the Martian mantle.

"We've never seen the inside of a planet in such fine detail and clarity before," said the study's lead author, Constantinos Charalambous of Imperial College London. "What we're seeing is a mantle studded with ancient fragments. Their survival to this day tells us Mars' mantle has evolved sluggishly over billions of years. On Earth, features like these may well have been largely erased."

The InSight lander, which placed the first seismometer on Mars' surface in 2018, has recorded 1,319 marsquakes during its mission, providing the detailed data that made these findings possible, according to NASA.