NASA and the European Space Agency (ESA) aim to bring back to Earth soil and rocks collected on Mars. The Airbus company is studying Sample Fetch Rover which will be responsible for recovering the valuable samples.
Mars is the planet to which we have sent the greatest number of robotic explorers. However, if the analytical instruments taken this time appear remarkable, they meet severe constraints in terms of mass, volume and electrical consumption. They therefore cannot match what can be done in terrestrial laboratories. That’s why we have been thinking for years about how to bring back to Earth samples of the soil and rocks from Mars. And this approach is currently underway!
A Mission in Several Stages
A complex destination to reach, the red planet is just as demanding when it comes to leaving it. To make a mission known as Mars Sample Return a reality, NASA and the European Space Agency (ESA) have designed an approach in several stages. The first stage is to collect the samples from Mars, then prepare them so they can be deposited on the ground, where another craft will come for them. A distant future? No, since, in fact, the rover responsible for the first stage, sampling, will take off this summer on 20 July (the window for take-off extends until 11 August). It’s called Perseverance, NASA’s Mars 2020 mission. The video below from the American agency explains the operation known as a “sampling caching system.”
This complex mechanism gives Perseverance the ability to put aside samples of soil or rocks in 43 tubes which will be hermetically sealed. NASA’s rover has a storage space, but the aim is to deposit up to 36 of them, carefully selected by scientists, on the Mars surface at one point in its mission. Another rover will then come on the scene, called Sample Fetch Rover, responsible for going to retrieve them to start their journey to Earth. It stands to reason, given the word “Fetch” in the name.
Airbus is Studying the Sample Fetch Rover
The Sample Fetch Rover will arrive on Mars on a separate NASA mission from Perseverance. Cooperation between the American Agency and ESA means that this rover will be European and, on 16 June 2020, Airbus won the study contract for it.
Basic Scenario of the Mars Sample Return. First of all, “Mars 2020 Mission” (on the far left) will take Perseverance to the red planet, with its ability to seal samples in tubes and deposit them on the ground. Then “Sample Retrieval Lander Mission” will take off. Its Sample Fetch Rover (European) will collect the tubes left by Perseverance and will carry them to a little launcher responsible for putting them into orbit around Mars. The third stage involved is European and it is called “Earth Return Orbiter Mission.” This craft will intercept the samples previously placed in Mars orbit so that they can be brought back to Earth. All three stages could be carried out by 2031.
Credit: ESA- K. OldenburgThe Sample Fetch Rover’s function will therefore be to pick up the tubes created by Perseverance like Tom Thumb. For ESA, Airbus has to design a rover which will prioritise speed of travel, since 200 m per day are scheduled so that 15 km can be crossed in 6 months. A robotic arm will be used to lift the samples left on the ground. Below, an ESA video showing the Sample Fetch Rover.
It will be noted that we are talking about a fairly big mobile machine, since Airbus’s illustration below shows that it is as big as a supermini car.
Once the samples are collected, the European rover will take them to the landing platform, thanks to which it arrived on the red planet. This platform houses a little launcher. A robotic mechanism will transfer the tubes which contain soil and rocks from the rover into a capsule which the little launcher will put into orbit. This capsule will be the size of a basketball.
However, the little launcher will not have the power required to send the samples directly to Earth. A third mission will therefore be required, by ESA, on which a probe will recover the “Basketball” in Martian orbit before starting the journey to our planet.
The ESA video below summarises all the stages of Mars Sample Return.
You will note that this video from 2018 shows a Sample Fetch Rover with 6 wheels. The current concept called for four larger wheels so that (according to Airbus) we can “guarantee the speed and performance required to reach the tubes and bring them back in the time allotted to the launcher.”