NASA's Curiosity rover hasn't even been on the red planet for a month yet and the agency has already announced its next plans for a Mars expedition.
While Curiosity is gathering surface samples and taking images like never seen before on Mars, NASA wants to go deeper -- literally. The agency calls this next phase, for which it plans to send another robot to the planet by 2016, "InSight."
"We are certainly excited, but our veterans on this team know the drill," Tom Hoffman, project manager for InSight from NASA's Jet Propulsion Laboratory in Pasadena, Calif., said in a statement. "Which is fortunate, because one of the great things we'll get to do on Mars is drill below the surface."
The space agency decided Monday to launch a relatively low-cost robotic lander in 2016 to check out what makes the Martian core so different from Earth's.
The interior of Mars is a mystery. It has no magnetic field, and scientists aren't sure if the core is solid or liquid or even has frequent quakes like Earth.
"What kind of Mars quakes are there? How big is the core of Mars? Does it have remnants of a molten core like the Earth does?" asked Discovery program chief Lindley Johnson.
Here's more on the tech that will help answer this questions within the next few years:
Drilling underneath the red Martian topsoil will be courtesy of InSight's HP3, or Heat Flow and Physical Properties Package – one of the four instruments the Mars lander will carry. Made by the German Aerospace Center, or DLR, HP3 will get below Mars' skin by literally pounding it into submission with a 14-inch (35-centimeter), hollowed-out, electromechanically-festooned stake called the Tractor Mole.
"The Tractor Mole has an internal hammer that rises and falls, moving the stake down in the soil and dragging a tether along behind it," said Sue Smrekar, deputy project scientist for InSight from JPL. "We're essentially doing the same thing any Boy or Girl Scout would do on a campout, but we're putting our stake down on Mars."
The German-built mole will descend up to 16 feet (five meters) below the surface, where its temperature sensors will record how much heat is coming from Mars' interior, which reveals the planet's thermal history.
"Getting well below the surface gets us away from the sun's influence and allows us to measure heat coming from the interior," said Smrekar. "InSight is going take heartbeat and vital signs of the Red Planet for an entire Martian year, two Earth years. We are really going to have an opportunity to understand the processes that control the early planetary formation."
Watch NASA's video about the mission:
The mission will be run by NASA's Jet Propulsion Lab. The California lab is basking in the success of the $2.5 billion Mars Curiosity rover, which is starting to explore the planet's surface after a daring landing this month. Earlier this year, NASA pulled out of two Mars missions with the European Space Agency because it didn't have the $1.4 billion for the proposed 2016 and 2018 mission.
NASA is still working on another possible Mars mission to replace the canceled ones with a decision later this month.
That's just "too much emphasis on Mars in our current plans for planetary exploration," said Carolyn Porco, a prominent scientist who studies Saturn and its moons. "Most of the solar system resides beyond the orbits of the asteroids. There is more to learn there about general planetary processes than on Mars ... Why more Mars?"
The Associated Press contributed to this report.