On October 19, the Schiaparelli probe crashed on the surface of Mars.
Ever since the impact, the European Space Agency (ESA) has been carrying out an extensive investigation to understand why the landing attempt failed. What precisely triggered its landing engines to prematurely shut down, causing it to fatally crash and explode on the Red Planet?
The investigative team learned that the separation between the Schiaparelli probe and the Tras Gras Orbiter (TGO) went as planned, as well as the atmospheric entry. The parachute deployed at 7.5 miles (12 km) above the surface at a speed of 1,075 mph (1,730 km/h).
During the descent, the altitude was meticulously tracked by the navigation system’s radar Doppler altimeter. The rotation rate of the Schiaparelli lander was measured by the Inertial Measurement Unit (IMU). For only one second, the IMU recorded a rotation that was too high. This erroneous data caused the IMU to go beyond its measurement parameters, and led the navigation system to conclude that the lander was not only on the surface of Mars, but below ground level.
This misinterpretation caused the Schiaparelli to jettison its parachute at an altitude of 2.3 miles (3.7 km), firing its thrusters for only a few seconds. After the thrusters stopped prematurely, Schiaparelli went into free fall before exploding onto the dusty surface below. Computer simulations have successfully reproduced this outcome given the same inaccurate data to the control system.
A statement from David Parker, ESA’s Director of Human Spaceflight and Robotic Exploration, sheds more light onto the investigation and Schiaparelli’s lasting contribution: “The full picture will be provided in early 2017 by the future report of an external independent inquiry board, which is now being set up, as requested by ESA’s Director General, under the chairmanship of ESA’s Inspector General. But we will have learned much from Schiaparelli that will directly contribute to the second ExoMars mission being developed with our international partners for launch in 2020.”
Below you can see Schiaparelli’s crash site from the perspective of NASA’s Mars Reconnaissance Orbiter.
Filed Under: Aerospace + defense