Of all the bits and pieces we sent on that 54.6 million-kilometre journey to Mars aboard a nuclear-powered robot, a drill was one of the most important. To find out if there are organic molecules lodged inside the rocks of Mars from when they formed, we need to analyse dust from below the surface of the red planet, which is what NASA scientists are in the process of doing right now. But how exactly do you drill down into a faraway planet, and then poke around in the dust - remotely - from millions of kilometres away? In the latest episode of Smarter Every Day, Destin takes us to NASA's Jet Propulsion Laboratory (JPL) to find out.

First we meet Mark Rober, a mechanical engineer at JPL who was part of the team that engineered this amazing moment back in 2012, when the Curiosity rover was set down on the Martian surface by some fancy rocket cranes. We head on over to the 'Mars Yard', which is a real-life simulation of the Martian surface, and home to a Curiosity rover that's an exact, working replica of the one sent to Mars. "This is one of a kind. The only one on planet Earth," says Rober, before Destin corrects him. 

"I guess it's two of a kind," he points out. Touché.

The Curiosity duplicate exists so scientists can test various software updates and tricky manoeuveres before they attempt them remotely on Mars. Destin tries not to geek-out too hard (he fails) as he runs through the various parts of the rover for us to see, including the drill bit, the back-up drill bits, and sample collector.

Next we get to see how the drill bits attached to the Curiosity rover would have actually dug down into the Martian surface, thanks to our handy replica of its rocky surface in the JPL yard. Something the scientists behind Curiosity need to be cautious of is if Mars is slightly wet underneath - which it appears to be - this can cause the dust particles to get sticky and jam the drill bit. We meet Ryan, a drill systems engineer at JPL, who shows us exactly how they get around that one.

The final piece of the puzzle is what actually happens to the dust particles after the rover's drill does its job. I'll let Destin run you through that because he does such an awesome job, and you really do need to meet all the scientists he's been talking to at NASA. Watch the latest episode of Smarter Every Day above, and send out some thoughts to the original Curiosity rover on Mars. It must get pretty lonely out there sometimes.