19, marking the first time a science instrument has ever been placed onto the surface of another planet. The lander is set to study the interior of Mars and listen for marsquakes. Details: https://go.nasa.gov/2EDHdXt

19, marking the first time a science instrument has ever been placed onto the surface of another planet. The lander is set to study the interior of Mars and listen for marsquakes. Details: https://go.nasa.gov/2EDHdXt