What does Mars feel like?

In 2020 the European Space Agency is preparing to launch a rover that will touch down on and explore both above and below the surface of Mars, looking for signs of life. But, to make sure that it can cope with any of the terrains it encounters, the designers at Airbus Defence and Space, in Stevenage, have built a special environment to recreate what lies in wait for the rover. Izzie Clarke went to take a look...

Izzie - As I walked through Airbus Defence and Space, I saw towering warehouses full of spacecraft motors and fuel tanks, workshops waiting to transform telescopes and, at it’s centre - Mars. Well, sort of…

Elie - This is as close to Mars as we can get within the constraint of this facility.

Izzie - Dr Elie Allois is a mission and robotics engineer for the advanced concept team at Airbus. We sat on a viewing platform overlooking the Mars yard…

Elie - This facility has been purpose built for the ExoMars rover. This is the first European rover that will be launched in 2020 and will look for traces of life on Mars.

Izzie - We can’t even touch Mars, how has this been designed, and created, and tailored to be as close to it as possible?

Elie - There’s been a number of missions to Mars already and the American rovers have experienced a lot of different conditions, such as very soft sands in which we could get bogged down like the Spirit rover that got stuck and that killed the mission, to the Curiosity rover that experienced a lot of sharp rocks that affected the structural integrity of the wheels. But, from the data we’ve got so far, we’ve been able to recreate a landscape with rocks, with textures, with sand, with the right colour and complexity as Mars to tailor the guidance and control algorithms for the rovers.

Izzie - I can see that we’ve got a rover set up in that room so are we able to go and explore that?

Elie - Yes. Let’s go.

Izzie - (Oh, I think I’m sinking a little bit). The converted hangar was filled with a course, golden yellow sand. That’s right - a red planet with a yellow surface, along with red, blue, orange, and white rocks of different sizes. Whilst it didn’t feel as razor sharp as Mars’s actual sand, it was gritty and rough, certainly not the type you’d want to find on a beach. It’s here in the Mars yard that the Airbus team will carry out tests to control Bruno, the ExoMars 2020 rover. You can hear him clanking about as he roamed across the yard. It’s his job to explore the red planet for any indicators of life, searching for signs of water, drilling through the surface as he goes.

Elie - The ExoMars rover - the mission is going to drill down to about two metres. We’re not going to carry a two metre drill, what we’re doing is actually carrying a drill built on the same principle as an oil rig. It is made of sections that you can fit one into the other up the maximum length of about two metres.

Izzie - Is there any particular reason why you’re looking into two metres, why not just explore the surface and go feeling around there?

Elie - This is a good question. What we want to do is explore below one metre on the surface of Mars. To date, the science seems to indicate that the top one metre will be ionised with radiation from the cosmos and the Sun and, therefore, is not really a good place to look for traces of life. So what we want to do is to go below this one metre, and go even further and go up to two metres.

Izzie - When you say life, are we talking about people as we know you and I or are we talking about little molecules that might lead on to something bigger?

Elie - I think life, in this instance, would understood as almost microorganisms. We’re really talking about minute elements, minute systems that can actually live there on the planet. We are not really expecting any developed life like you and I but, you know, this is really the early days of our research in the cosmos.

Izzie - Whilst the team aren’t on the lookout for martians, they’ll be searching for any signs of water and minerals with the use of next generation instruments. This includes an infrared spectrometer which can be used to study and identify chemicals within the borehole. Once collected, a sample is delivered to the rover’s analytical laboratory…

Elie - ExoMars, in the grand scheme of things, is a stepping stone towards the next big milestone in planetary exploration, which is going to be a Mars sample return mission.

Izzie - In a sample return mission, one rover would go to Mars, dig around, package up samples and leave them on the surface of the planet. A second mission would send another rover to scoop these up and bring them back to us on Earth. But what if a rover get’s stuck?

Elie - Hazards can be a lot of things. You can have a visual hazard that you can detect like a big rock is in the way. You don’t want to fall down a crevice or a canyon but, at the same time, you want to avoid locations where you might have some crust on the top that is just covering a layer of very soft sand. This is the worse possible case where you can actually dig yourself in. So we’re looking at different concepts to avoid these situations.

One of them is to send a smaller scout rover to prod the ground ahead of this primary rover and to give a bit of a rating of the suitability of the terrain for the main rover to traverse. Alternatively, what we could do is try to build this kind of sensing inside the main rover and, in the same way as you feel the sole of your shoe to detect whether you’re walking on gravel or sand, you could actually feel at the wheel level whether you are on solid ground, or whether it is something that is about to crack. So there is a number of ways we can do that.

Izzie - How far ahead are we envisioning this sort of mission?

Elie - A Mars sample return mission has been on the cards for quite some time, and we’re really looking at an actual sample return potentially in the mid 2020s, probably 2030s.

Izzie - So we’re not quite at the stage of building sandcastles on Mars. But, within the next few decades these huge missions will sift through the red planet’s surface and hopefully bring part of Mars back for us to hold here on planet Earth.