The search for life on Mars begins with ‘Charlie’ in Spain’s Almería desert

A team of engineers and scientists has brought a machine from the future to the Tabernas desert in Almería, Spain. In a landscape familiar to fans of Sergio Leone westerns, before the sun had truly warmed the ground, they lifted Charlie onto a small cart — the prototype rover that the European Space Agency (ESA), Airbus, and much of European industry and science have been designing for years. They took it to an area that alternated between very fine dusty soil, rocky scree and salt-encrusted ground. They wanted to test how the machine would cope in an environment as close as possible to Mars. That is the ultimate goal of the ExoMars mission to which it belongs: to reach the Martian surface in 2030 — after more than a year of space travel — with the first European rover to touch down there, and drill into it in search of past or present life on the red planet. At least in the dry Almería scrub, Charlie seems to have convinced the scientists.

“It’s an incredible replica; this is one of the best places in the world if we are looking for a faithful representation of the geology and terrain morphology we will find on Mars,” says Benoit Pouffary, chief exploration engineer and head of the ESA’s ExPeRT team, explaining why they decided to test the rover in Almería. ExPeRT is the ESA group’s acronym, a team dedicated to developing technologies and preparing for exploration of the red planet. Pouffary highlights that this part of the Almerían desert resembles “the specific area we will head to.”

Pouffary and the rest of the engineers have already spent two weeks here conducting tests and today is Charlie’s last day in Tabernas. During this time they have studied how the rover responded to the different terrains of this desert. While the rover’s eyes bring to mind the robotic protagonist of Pixar’s Wall-E (2008), its operators watched from far away. The mission control center is in Turin, Italy: the training was not only for Charlie but also for those who will operate it remotely. “Because we need to train teams in the most representative conditions possible, it is of utmost importance that the test environment resembles as closely as possible what they will encounter in reality,” the chief engineer explains.

Charlie is part of the ExoMars program, launched more than a decade ago. The program’s first mission did not end well, with the Schiaparelli module crashing into the Martian surface after passing through the planet’s thin atmosphere at about 540 kilometers per hour (335mph). But despite setbacks and delays, the loss of Schiaparelli, which was within engineers’ calculations, helped refine the design of the second phase of ExoMars, the Rosalind Franklin rover, of which Charlie is the prototype. That module was meant to test several critical entry, descent, and landing technologies on Mars, all European. Charlie must pick up where Schiaparelli left off: demonstrating that its design will allow safe exploration of the Martian surface without getting stuck or tripping.

But Charlie will not be the one to go to Mars. Neither it nor the four other rovers used to gather data for its sister, Rosalind Franklin, will go. “But it has the same wheels, the same mast, the same base,” notes Jeremy Close of Airbus, the company leading the rover’s manufacturing and design, together with British, German, and French universities and the Swiss Space Agency, as well as the ESA. What the prototype is learning in Almería will be incorporated into Rosalind Franklin. The rover is scheduled to be launched in 2028. Once on the Martian surface, in early 2030, it will have to drill to about two meters deep and recover any material it finds.

“Below the surface, whatever is there is better protected from events such as radiation,” recalls Vincent Schaeffer, an Airbus engineer and head of the Almería tests. “The rover will carry a laboratory capable of analyzing samples in situ to look for traces of life,” he adds. That and no other is the ultimate objective of the ExoMars mission: to find any sign of past or present life in the Martian subsurface.

To find where to drill, the mission rover will carry a suite of sophisticated instruments. Although Charlie did not carry them, one of the tests carried out in the Almería desert was crucial: testing its autonomous navigation system. Rosalind Franklin is expected to receive at the start of each sol (the term for a Martian day) a sort of agenda listing the tasks to be performed. But the rover itself will complete them autonomously and, at the end of each sol, report back to Earth. In Almería, Charlie was operated remotely from Turin. Although the 1,645 kilometers separating the Italian and Spanish cities are not the 55 million kilometers between Earth and Mars at their closest orbital positions, they were able to study how the rover responds to that freedom of action.

One detail illustrates the complexity of space exploration. On firm but uneven ground, Charlie demonstrated its skills to the 50 or so journalists following and photographing it as if it were a movie star on the Oscars red carpet. The movements of its six wheels, which can operate independently, were extremely slow, as if it knew it was walking across a minefield. It would have taken more than an hour to travel one meter. On Mars, the final rover will have six months to complete its mission.

Sign up for our weekly newsletter to get more English-language news coverage from EL PAÍS USA Edition