After the probe lands on Mars (all going well – and it sometimes doesn’t), it will use a robotic arm to deploy a “mole” to burrow up to five metres below the surface, leaving a long sensor-laden tail in its wake. There it will measure Mars’ vital signs: detecting how much heat is flowing from the planet core up to the surface.
This data, it is hoped, will deliver new insights into the anatomy of our nearest neighbour, and even hints at how the solar system came into being.
Fittock, 34, left school in 2001 and took a double degree at Monash University in astrophysics and mechanical engineering. It was an unusual but deliberate combination: he wanted to work on space tech.
And seven years ago he found himself at DLR, through “good luck or good opportunity”, he says, as “mole development test lead”.
That rolled into a job in a team of 25 as lead engineer for the surface segment, “Susanna” – the molehill on the surface that will deploy the mole, keep it safe, guide its journey and relay its readings back via the lander to Earth.
“Pardon the pun but we had to break a lot of new ground,” says Fittock.
They had a lot of trouble getting the mole to work reliably in the Martian environment.
“We just don’t know that well what we’re going into over there,” he says. It’s not like they could go and have a look.
“We can make guesses from what we can see from orbit, but once you go a little bit below the surface we have to make broader and broader guesses.
“We will be going where nobody has gone before.”
His team’s first challenge was getting the mole to dig deep enough to get good data.
The 1 kilogram, 30cm-long mole will thump and shake itself into the sand, driving through sand and rock and filling it in behind.
They built a “very skinny tall sandpit” to test how that was going to work.
“The short summary is, it’s really, really hard,” Fittock says.
“It took longer to dig than expected, and during that time it was damaging itself, because it thumps and thumps away. It was a big technical challenge, how could we make it more robust.”
They expect Mars’ gravity to give them a hand, making the sand looser than its Earth equivalent.
But they also expect to hit rocks.
“They picked a nice landing spot for us, one we should be able to dig into, and we will be able to avoid the rocks on the surface,” he says.
But there will be a “nail-biting moment”, he says, when they first see the surface they’ve landed on, and can be sure it’s something they can crack open.
Even if they can get the mole into the sand there are likely to be rocks below the surface. Some they can smash through, others they can travel around, but some could just prevent them altogether from reaching the desired 5 m depth.
The burrowing process, which begins next year, will be slow and painstaking. Whenever the mole hits a problem it will stop, allowing the team back home to analyse the situation and strategise.
Another problem, one entirely out of Fittock’s team’s control, is the landing.
He’s going to be out at a dinner with fellow space engineers.
“I’m going to be there with my phone trying to look professional while I’m sitting there nervous as hell about what happens at the landing. But it’s a big space dinner so I think everyone will want to see it.”
Risks aside, Fittock says he is pretty confident of getting “good science” out of his systems.
“We are going to get a better picture not just of what Mars is doing now, but also how was Mars formed, how did Mars get from the start of the solar system to now, and even a better understanding of our whole solar system.
“We sometimes underestimate how little we know about everything outside the Earth and even things here on the Earth.”
Fittock has since moved on to a new company, OHB in Bremen, as project leader on future space exploration missions
Currently he’s on a mission called Hera, working with NASA to go to an asteroid pair and smash a spacecraft into one of them.
It’s going to give them useful ideas about how – if an ‘Earth-killer’ asteroid is spotted coming towards Earth – we might be able to push it off its deadly aim.
“In the last few years we’ve learned that asteroids and comets are different to what we expected, in many fundamental ways,” Fittock says.
“We want to know what happens when this impact occurs.”
Nick Miller is Europe correspondent for The Sydney Morning Herald and The Age