https://www.cnet.com/news/nasa-insight-mars-landing-monday-lets-us-be-rocket-scientists-for-a-day/

InSight (short for Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) has set out to learn about the interior of the Red Planet and how it was formed, with the hope that we'll learn more about the origins of our own planet.  

It will drill deeper beneath the Martian surface than ever before to find out about Marsquakes and the interior heat of the planet. And by bouncing radio signals back and forth with Earth, it will tell us whether Mars wobbles on its orbit (ultimately telling us about the composition of the planet's core).