The NASA JPL Insight mission intends to put a lander on Mars in 2016. Its primary scientific focus will be on studying the Red Planet’s interior:  InSight mission to find what lies beneath Martian surface – Spaceflight Now

From the Insight Overview:

InSight (Interior Exploration using Seismic Investigations, Geodesy and Heat Transport) is a NASA Discovery Program mission that would place a single geophysical lander on Mars to study its deep interior. But InSight is more than a Mars mission – it is a terrestrial planet explorer that would address one of the most fundamental issues of planetary and solar system science – understanding the processes that shaped the rocky planets of the inner solar system (including Earth) more than four billion years ago.

By using sophisticated geophysical instruments, InSight would delve deep beneath the surface of Mars, detecting the fingerprints of the processes of terrestrial planet formation, as well as measuring the planet’s “vital signs”: Its “pulse” (seismology), “temperature” (heat flow probe), and “reflexes” (precision tracking).

Here’s an animation of the lander’s initial operations:

Members of the Insight team talk about the mission: