The European Space Agency (ESA) has reached a significant milestone in its ambitious ExoMars mission. The parachute system, essential for ensuring the safe landing of the Rosalind Franklin rover on Mars, has successfully passed a critical test. According to a recent ESA announcement, the complex parachute system, the most advanced of its kind, was deployed during a high-altitude test in Sweden. These parachutes, designed to withstand the unique conditions of the Martian atmosphere, are crucial for a smooth landing after a high-speed descent through the thin Martian atmosphere. This test, conducted at the Esrange Space Center in Kiruna, Sweden, represents a pivotal moment in the mission’s preparation, confirming that the parachute design will function effectively in the harsh Martian environment.

Groundbreaking Test at High Altitude

The parachute system underwent testing under simulated Mars-like conditions, where the Martian atmosphere is only 1% as dense as Earth’s. To replicate these challenging conditions, a stratospheric helium balloon lifted a mock-up of the ExoMars descent module to an altitude of nearly 30 km. This is about three times higher than where commercial aircraft typically cruise. As the mock-up capsule fell freely for about 20 seconds, it reached nearly the speed of sound before the parachutes deployed sequentially. This drop test was critical to confirm that the parachute system could effectively decelerate the spacecraft to a soft landing speed, mimicking the supersonic conditions it would face during its descent on Mars.

“We are happy to confirm that we have a parachute design that can work on Mars – an ambitious system with the largest parachute ever to be flown outside Earth,” says Luca Ferracina, ESA’s ExoMars Entry Descent and Landing Module system engineer. The test validated the parachute system’s capabilities and reassured mission teams that all components would perform as needed on Mars.

Dual Parachute Design for Mars Landings

One of the most crucial aspects of the ExoMars landing sequence is the use of a two-stage parachute system, which combines the strengths of both medium-sized and larger parachutes. The first parachute is a medium-sized, 15-meter-wide system designed to handle the deceleration of the module through supersonic speeds. This parachute is based on the same technology used in the Viking Mars missions of the 1970s and the Cassini-Huygens mission to Saturn’s moon Titan. The second parachute, however, is a much larger 35-meter-wide design, the largest parachute ever to be deployed outside Earth.

“Using two parachutes allows us to design a strong, medium-sized parachute to decelerate the probe through supersonic speeds and then a much larger, lightweight parachute for the final descent,” explains John Underwood, principal engineer at Vorticity, the UK company entrusted with parachute design and test analysis. This two-parachute design enables the probe to slow down efficiently, ensuring a smooth descent for the Rosalind Franklin rover, which will explore Mars’ surface in search of signs of past life.

The Challenge of Mars’ Atmosphere

Mars’ thin atmosphere poses unique challenges for landing technology, making it essential to test the parachutes under similar conditions before the mission takes place. The parachutes must deploy at precisely the right moment, with no room for error, as any malfunction could result in a catastrophic landing failure. These tests, while conducted on Earth, replicate the velocity and low atmospheric density of Mars, providing a high level of confidence in the parachutes’ ability to perform as expected.

“The combination of velocity and low atmospheric density in this test is exactly the same as what the parachutes will experience on Mars. Testing on Earth is a way to gain confidence and confirm that all the elements perform as expected,” explains Luca Ferracina. This approach ensures that ESA and its partners are well-prepared for the complexities of the mission, especially given the high-risk nature of Mars landings.

Long-Term Storage and Readiness Verification

One of the key challenges the ESA team faced in preparing the parachutes for the final test was their long-term storage. The ExoMars mission had been delayed due to external geopolitical factors, and the parachutes had been stored for an extended period. However, this did not deter the team from ensuring the parachutes’ readiness for Mars.

“We are running this campaign to confirm our readiness for Mars, and to verify that the parachutes are still performing as expected after the long storage,” explains Luca Ferracina. The successful performance of the parachutes after this extended period of storage was an essential step in finalizing the system’s readiness.

Data Analysis and European Expertise

Following the drop test, the parachutes were recovered for inspection, and high-speed video footage was analyzed to assess their performance. This approach allows the team to gather extensive data that can be used to refine the design and ensure optimal performance during the actual mission. “Testing on Earth has the advantage that we can obtain much more data and recover the parachutes for inspection after the test,” says John Underwood.

The European team behind the ExoMars parachutes represents the cutting-edge of space exploration engineering. The parachute system was developed across various European countries, including the Netherlands, Italy, and Czechia. Components like the deployment mortars were made in the Netherlands, the parachutes themselves were designed in Italy, and the parachute container was built in Czechia. Thales Alenia Space in France supervised the test campaign, ensuring the parachutes would meet the rigorous standards required for space exploration.