Communication Lost After Retro Thrusters Fired For A Shorter Time Than Expected

The thrusters designed to slow the ESA Schiaparelli Mars lander fired for less time than was anticipated as it descended toward the Martian surface, leaving the fate of the lander uncertain.

Contact with the vehicle was lost shortly before the module was expected to touch down on the surface, according to a news release from ESA. Discrepancies between the two data sets are being analysed by experts at ESA’s space operations centre in Darmstadt, Germany.

Early indications from both the radio signals captured by the Giant Metrewave Radio Telescope (GMRT), an experimental telescope array located near Pune, India, and from orbit by ESA’s Mars Express, suggested the module had successfully completed most steps of its 6-minute descent through the Martian atmosphere. This included the deceleration through the atmosphere, and the parachute and heat shield deployment, for example.

The detailed telemetry recorded by the Trace Gas Orbiter was needed to better understand the situation. At the same time as Schiaparelli’s descent, the orbiter was performing a crucial ‘Mars Orbit Insertion’ manoeuvre – which it completed successfully. These important data were recorded from Schiaparelli and beamed back to Earth in the early hours of Thursday morning.

The data have been partially analysed and confirm that the entry and descent stages occurred as expected, with events diverging from what was expected after the ejection of the back heat shield and parachute. This ejection itself appears to have occurred earlier than expected, but analysis is not yet complete.

The thrusters were confirmed to have been briefly activated although it seems likely that they switched off sooner than expected, at an altitude that is still to be determined.

“Following yesterday’s events we have an impressive orbiter around Mars ready for science and for relay support for the ExoMars rover mission in 2020,” said Jan Wörner, ESA’s Director General.  “Schiaparelli’s primary role was to test European landing technologies. Recording the data during the descent was part of that, and it is important we can learn what happened, in order to prepare for the future.”

“In terms of the Schiaparelli test module, we have data coming back that allow us to fully understand the steps that did occur, and why the soft landing did not occur,” David Parker,ESA’s Director of Human Spaceflight and Robotic Exploration.

“From the engineering standpoint, it’s what we want from a test, and we have extremely valuable data to work with. We will have an enquiry board to dig deeper into the data and we cannot speculate further at this time.”

(Source: ESA news release. Images provided by ESA and from file)

FMI: www.esa.int