What's inside Mars?
We know a lot about what's inside Earth.
But at Mars, we've only just scratched the surface.
To learn how Mars formed, we have to study its deep interior.
NASA's InSight lander was designed to do just that by taking the planet's "vital signs":
- Listening for its "pulse" or seismic activity, including any "Marsquakes"
- Taking its temperature to see how much heat is flowing out from deep inside
- And checking its "reflexes" to see how much the planet wobbles as it whips around the Sun.
These all provide clues to what the planet is really like inside.
So what's inside Mars?
InSight can help us find out by giving Mars its first thorough checkup since it formed 4.5 billion years ago.
The more we learn, the better we'll understand all the rocky planets -- and the history of our solar system.