The European Space Agency’s ExoMars rover left its Airbus factory in Britain on Wednesday, heading for a round of testing in France before integration with its carrier and descent modules on pace for launch toward the Red Planet next July.
The nearly-complete rover is the centerpiece of the ExoMars mission, a joint robotic exploration project between ESA and Roscosmos, the Russian space agency.
The rover is named for Rosalind Franklin, a British chemist and X-ray crystallographer whose work contributed to the discovery of the twisting double helix shape of DNA molecule.
“Completing the build of the Rosalind Franklin rover under the strict cleanliness requirements, with all the science instruments onboard, is a major milestone of our ExoMars program,” said David Parker, ESA’s director of human and robotic exploration, in a statement. “It is thanks to the dedication of all the teams involved that we are able to celebrate this moment today.”
“We’re looking forward to completing the final rounds of tests before the rover is declared flight ready and closed inside the landing platform and descent module that will deliver it safely to the surface of Mars,” Parker said.
The Rosalind Franklin rover is Europe’s first Mars rover.
In launch configuration, the solar-powered robot weighs nearly 700 pounds (about 300 kilograms). The European rover is smaller than NASA’s Curiosity rover currently exploring Mars — along with NASA’s Mars 2020 rover set for launch next year — and somewhat larger than the Spirit and Opportunity rovers that landed on the Red Planet in 2004.
Teams at Airbus Defense and Space’s facility in Stevenage, England, north of London, assembled the Rosalind Franklin rover in a special ultra-clean factory over the last 18 months. The construction work capped more than a decade of design — and redesign — activities to prepare the ExoMars rover for its flight to Mars.
Airbus teams built the rover under strict cleanliness requirements, on top of the clean room standards for a typical space mission.
“The goal of ExoMars is to find life on the surface, more specifically under the surface, of Mars, and that means that we absolutely cannot take anything organic with us,” said Paul Meacham, the rover’s lead systems engineer at Airbus. “So that informs things like material choices. The wheels on the rover, for example, are metallic rather than being made of rubber. But that also means that when people are working on it, they must not in any way organically contaminate the rover.”
Over the last few months, engineers installed the rover’s scientific instruments, drill, a 3D panoramic camera suite, solar panels and wheels.
The Rosalind Franklin rover’s scientific payload includes instruments from Europe and Russia, with some component contributions from NASA. The instruments will study the make-up of the rocks and soil around the rover on Mars.
Teams at Airbus also installed the rover’s Analytical Laboratory Drawer, an instrument box which holds equipment to deliver rock and soil samples to three scientific instruments housed inside the container.
The rover’s six metallic wheels and drive system come from MDA in Canada, a division of Maxar Technologies.
The United Kingdom is the second-biggest financial contributor to the ExoMars program among ESA member states, after Italy, so Airbus’s Stevenage factory won the rights to the rover development.
After leaving Airbus’s Stevenage plant, Rosalind Franklin rover’s next stop is at Airbus’s satellite factory in Toulouse, France, where it is due to arrive by truck Friday.
In Toulouse, engineers will place the rover on a vibration bench and in a thermal vacuum test chamber to verify the robot can withstand the rigors of spaceflight and the frigid environment of Mars, where temperatures will drop to minus 184 degrees (minus 120 degrees Celsius) outside, and minus 76 degrees Fahrenheit (minus 60 degrees Celsius) inside the rover, according to ESA.
The carbon dioxide-rich Martian atmosphere is about 100 times thinner than Earth’s.
The test campaign in Toulouse should last about four months, assuming everything goes according to plan, then officials will ship the rover to Thales Alenia Space in Cannes to meet the ExoMars mission’s German-built cruise stage and Russian descent module.
Engineers mated the cruise stage and descent module for the first time this week at a Thales Alenia Space facility in Turin, Italy, where the hardware will undergo its own test series over the coming months before shipping to Cannes, where engineers will add the rover.
While the major pieces of the ExoMars mission are coming together in Europe, engineers are struggling to confirm the readiness of the lander’s parachutes, which will slow the spacecraft before touchdown on Mars. The two most recent ExoMars parachute tests — in May and earlier this month — resulted in tears to the chutes.
On the most recent test, conducted over Sweden on Aug. 5, the largest of the four parachutes needed to deliver the ExoMars lander to the surface of Mars suffered damage to its canopy. As a result, the test vehicle used in the parachute test descended under the aerodynamic drag of only the much smaller pilot chute, ESA said.
Read our earlier story on the ExoMars parachute testing.
Two more parachute tests are planned later this year and in early 2020. If both tests produce satisfactory results, ESA officials will give the green light to ship the ExoMars spacecraft to the Baikonur Cosmodrome in Kazakhstan for final launch preparations.
ESA says the launch window for the ExoMars lander and rover opens July 26, 2020, and runs for less than three weeks. If the mission misses next year’s window, the next launch opportunity is in 2022.
The ExoMars program consists of two parts.
The ExoMars Trace Gas Orbiter launched in March 2016 on a Russian Proton rocket and is now surveying the Martian atmosphere with suite of scientific instruments to search for methane, and a camera to map changes on the planet’s surface. The Trace Gas Orbiter launched aboard a Russian Proton rocket in tandem with a landing craft named Schiaparelli, which crashed on the Red Planet on final descent.
Like its orbiter precursor, the second ExoMars mission will launch on a Russian Proton booster from Kazakhstan.
After landing, the Russian descent stage will remain operational as a stationary lander platform — named Kazachok, Russian for “little Cossack” — to conduct its own scientific measurements, while the European rover will drive several kilometers and drill to a depth of 2 meters (6.6 feet) to collect core samples for analysis in the mobile robot’s on-board laboratory.
Scientists have never studied material from so deep below the Martian surface, where biomarkers and organic molecules could survive from life forms that may have inhabited the planet when it was warmer and wetter billions of years ago.
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